Blog by Solar Energy UK member GivEnergy.

By now, you’ve likely heard about the Future Homes Standard becoming mandatory in 2025. The initiative sets out minimum energy efficiency requirements for all new homes built in England – with a view to improving both the economy and sustainability of home energy usage.

Unfortunately, the Future Homes Standard has a glaring omission. While factors such as insulation, air tightness, and low-carbon heating systems are (quite rightly) addressed – the directive fails to consider the pivotal role of energy storage.

This oversight comes to the detriment of both the billpayer and the UK’s net-zero emissions target. By missing energy storage, the Future Homes Standard is missing a key opportunity to make further efficiency gains.

What is the Future Homes Standard?

The Future Homes Standard (FHS) is a government directive that seeks to decarbonise new homes. As part of its bid to improve home energy efficiency, the initiative also reduces energy bills for the homeowner – helping ease the country’s mounting fuel poverty concerns.

The FHS primarily focuses on three key areas:

· Improving heating

· Improving hot water systems

· Reducing heat waste

So, it includes rules on building fabrics, insulation levels, triple glazing standards, ventilation rates, and low-carbon heating. (Heat pumps or solar thermal systems, for instance.) The FHS also seeks to mitigate overheating, stating that any potential overheating issues should be identified at the design and pre-construction stage.

Combined, then, these rules ensure that no new home built under the Future Homes Standard will be reliant on fossil fuels. This heightened efficiency is undoubtedly a great step – and one that we welcome. Yet the fact remains that it is a step too small.

To meet its ambitious emissions reduction targets, the government must stop overlooking battery storage. As an absolute minimum, it needs to integrate adequate energy storage provisions into the Future Homes Standard.

The role of energy storage

Battery storage technology has advanced significantly in recent years. It now represents a key component of any low-carbon energy system. Simply, without a storage battery, even so-called “efficient” homes will inevitably end up wasting energy.

It’s a little-known fact that, without storage, much of the energy generated by renewables goes to waste. Indeed, some two-thirds of the world’s energy is wasted between generation and usage.

Plus, this concept of waste aside, a lack of storage means that homes can only use any renewable energy intermittently – as and when weather conditions are favourable.

This, then, is when home storage batteries become essential. Batteries allow households to store excess electricity generated from renewable sources such as solar panels and wind turbines, enabling them to use this energy when it is needed. (And not just when the sun is shining, or the wind is blowing.) Firstly, having this excess energy stored for later use drastically cuts energy bills. From an environmental perspective, however, it also eases demand on the grid – thereby reducing carbon emissions.

Plus, even without renewables in place, a home storage battery still plays an essential role in clean energy management. Modern batteries – like those manufactured by GivEnergy – are designed to work strategically with smart energy tariffs. So, this means that they will charge intelligently using off-peak rates – storing energy only when it’s super cheap and green to do so. Then, in turn, they will discharge when energy costs are high. The home can run on battery power, instead of drawing from the grid when it’s at its costliest and dirtiest.

You would be right in thinking that all of the above makes energy storage a no-brainer inclusion in the Future Homes Standard. So, why is there no mention of home storage batteries in the government directive?

A continued lack of attention

For all the gains made over the past five years, energy storage still remains neglected at government level. The Future Homes Standard is a continuation of a pattern – not an exception to the rule.

For example, the British Energy Security Strategy furthers support for new nuclear, offshore wind, and heat pumps. Yet the deliverance of a complementary energy storage strategy is nowhere to be found.

More recently, following on from the Treasury’s reduction in VAT on renewables to 0%, the government is now reviewing whether to extend this VAT rule to include battery storage systems. However, even should this extension go ahead, it looks likely that it won’t apply to new installations or to standalone home batteries installed without renewables. Once again, then, a key opportunity to strategically embed energy storage into sustainable homes is somewhat short-sighted.

Perhaps more worrying is data from Cornwall Insight. Their research suggests that the government must invest £20bn in battery storage by 2030 to meet its renewables goals – which is almost a fifth of the government’s total investment in energy technologies.

As you can see then, energy storage is a broadly (and woefully) overlooked component in supporting the UK’s clean energy transition – of which the Future Homes Standard is just one part.

Powering change

Battery storage technology plays a significant role in reducing home carbon emissions. So, a forward-thinking government should update the Future Homes Standard to reflect this plain truth.

With energy storage capacity in the home, intermittent renewable energy becomes easier to harness and use consistently. Even without renewables, a home battery still allows homes to run on clean, off-peak battery power. Either way, then, the result of energy storage is that households can reduce their reliance on peak grid electricity – which is often generated from fossil fuel sources. In turn, households boast less waste, lower costs, and greener and more efficient energy usage.

To accelerate the transition to a low-carbon energy system, the UK government must stop overlooking home storage batteries. What better place to begin than the Future Homes Standard?

About the author

Jason Howlett is CEO at GivEnergy – the company empowering energy freedom for all. GivEnergy is the largest British-owned manufacturer of residential and commercial battery storage systems. As well as batteries, the company’s range also includes inverters, EV chargers, energy management software, and a host of supporting accessories. Together, these products create an ecosystem for customers to control their energy end-to-end.

Blog by Solar Energy UK member GivEnergy.

The UK government has enshrined in law a commitment to achieve net zero carbon emissions by 2050.

Part of this goal involves the full decarbonisation of power by 2035 – shifting from fossil fuels towards renewable energy, e.g. wind, solar, hydropower, etc.

On this front, significant progress has already been made, despite the recent announcement on allowing new gas plants to be built in the 2030s.

From 2010-2022, UK electricity generation from renewables grew from 26TWh to 135TWh. While this progress is commendable, it will count for little if the development of battery storage does not keep pace.

Use of battery storage at both grid and consumer level is a vital step to net zero. Energy storage helps offset the hour-to-hour variability of some renewables, and facilitates the increasing electrification of transport and heating (EVs, heat pumps, etc.)

Here, Dave Roberts, GivEnergy MD, explains the role of battery storage in the UK’s net zero mission.

Why is battery storage necessary to achieve net zero?

According to a report co-authored by Centre for Net Zero, consumer electricity demand in the UK is set to increase by around 50% by 2035.

This is being driven in large part by the electrification of:

• Transport – i.e., the increase in electric vehicles. The government plans to ban the sale of petrol and diesel cars by 2035.
• Heating – The government aims to increase installations of heat pumps to 600,000 per year by 2028. (Installation of traditional gas boilers in new build homes will be banned from 2025 onwards as part of the Future Homes Standard.)

Moreover, the renewables on which the UK is increasingly dependent – especially wind and solar – tend to have hour-to-hour variability. You can’t make the wind blow or the sun shine as and when required.

With battery storage, however, renewable energy can be stored and then discharged for later use. (Such as during times of peak energy demand.)

• Grid-Level

For a grid-level example of why renewables need battery storage, consider that during the winter of 2022-2023, the UK wasted enough wind energy to power 1.2 million homes. In short, an abundance of the wind energy generated had nowhere to go.

• Consumer-Level

To understand this problem at a consumer-level, take the following (all-too-common) scenario.

A household installs solar PV panels. During the day when the sun is shining, renewable energy is being generated. However, this is also the time when nobody’s home and therefore, electricity usage is low.

During the evening is when electricity demand peaks. Unfortunately, this is not when the sun is shining.

Without battery storage, there is no way for the household to store the solar energy generated during the day to be discharged later in the evening.

The role of grid-scale battery storage

The International Energy Agency (IEA) acknowledges that grid-scale storage is crucial for short-term balancing, as well as long-term energy storage.

The IEA also notes the following:

• Pumped-storage hydropower is still the most widely-deployed storage technology, but grid-scale batteries are catching up (battery storage capacity stood at around 28GW at the end of 2022)
• Grid-scale battery storage ‘needs to grow significantly’ to meet flexibility needs in a decarbonised electricity system
• To achieve net zero targets, grid-scale battery storage will need to increase to around 970GW by 2030

In a research paper by the Department for Energy Security & Net Zero, the UK government recognises the potential of the following types of storage batteries:

• Lithium-ion batteries (1-8 hours storage time)
• Flow batteries (4-8 hours storage time)
• Zinc batteries (1-6 hours storage time)
• Sodium sulphur batteries (1-6 hours storage time)
• Iron air batteries (up to 100 hours storage time)

Grid-scale battery storage in the real-world

Fortunately, this recognition is rapidly turning into real-world implementations. For example, the EnergyPulse Energy Storage report released in December 2023 by RenewableUK suggests that the pipeline of UK battery storage projects has grown by two-thirds over 12 months.

Capacity has gone from 50.3GW at the end of 2022, to 84.8GW a year later. (Including projects in the pre-planning, planning, consented, under construction, and operational stages.)

Meanwhile, according to a report by Aurora Energy Research, Britain is set to quadruple its grid-scale battery storage capacity by 2030.

And we can see this happening right now, in any one of many prominent examples. Take the grid-scale battery storage site in Pillswood, near Cottingham, East Yorkshire. The £75 million site can provide 196MWh of electricity in one cycle. That’s enough for 300,000 homes in Yorkshire.

The role of consumer-scale battery storage

Alongside grid-scale battery storage, a report by Centre for Net Zero also acknowledges the integral role that consumers can play in helping to achieve net zero targets through energy storage. Simply, storage needs to be implemented en masse in individual homes, too.

Some of the necessary infrastructure is already in place. In fact, according to figures from the Microgeneration Certification Scheme (MCS), around 1.3 million UK homes now have solar panels. For some, a wind turbine for home is also an option, though this comes with barriers regarding cost, practicality, planning permission, etc.

While this progress towards consumer-scale renewables is a step in the right direction, it’s not enough. Complementary battery storage is also necessary to ensure that energy generated isn’t wasted.  

Moreover, standalone battery storage (i.e., home battery storage without solar) can also bring benefits to the grid. Consumers on smart tariffs can charge during cheaper off-peak hours and discharge during peak hours. In turn, this helps to reduce strain on the grid when demand is at its highest.  

Consumer-scale battery storage in the real-world

The most recent available figures from 2019 show there were 10,000 home battery installations in the UK, though we can reasonably assume this has increased since then. 

Globally, the home battery storage market reached a capacity of around 34GWh by the end of 2023, according to Bloomberg. The market is expected to grow from a value of around USD5.4 billion in 2023 to around USD17.5 billion by 2028.

And this emerging market is already making a huge difference. Indeed, the ability of consumers in Great Britain to help balance grid demand has already been demonstrated through the Electricity System Operator’s (ESO) Demand Flexibility Service.

Introduced in the winter of 2022-2023, the Scheme rewards households and businesses for shifting electricity usage outside of peak hours. According to the ESO, over 3,300MWh of electricity was saved – enough to power 10 million households.

During the 2023-2024 Demand Flexibility Scheme, GivEnergy customers were able to participate. As part of GivBack, households could get paid to export the excess energy stored in their batteries during peak hours, ultimately helping to reduce strain on the grid.

GivEnergy CEO, Jason Howlett has previously advocated for the inclusion of battery storage in the Future Homes Standard (FHS) set to be introduced in 2025.

And according to a recent poll, this inclusion is supported by 61% of MPs. In the same poll, 79% of MPs supported mandatory solar panels in new build homes. As of press time, a consultation is ongoing.

A price drop for home storage batteries

While the specific details of the FHS regarding solar and storage hang in the balance, one thing is clear: home storage batteries are getting cheaper.

This is thanks, in part, to the UK government’s introduction of 0% VAT for the following:

• Battery storage coupled with solar
• Standalone battery storage
• Retrofit storage batteries

This will help make battery storage at consumer-level more accessible, and ultimately help enable consumers to contribute to balancing grid demand.

The pivotal role of battery storage in achieving net zero

It’s clear that for the UK to achieve its net zero mission, battery storage is essential at both grid- and consumer-level.

With the electrification of transport and heating, as well as the hour-to-hour variability of renewables, battery storage is essential in helping to balance grid demand.

Huge progress has already been made. This is true regarding the increasing number of grid-scale battery storage projects in the UK, as well as measures to encourage the uptick of consumer-level battery storage systems.

At the same time, we recognise that there are areas where further progress could be made. This includes the addition of mandatory battery storage in the FHS. 

Simply put, achieving the UK’s 2050 net zero targets will depend on battery storage. We need both large-scale battery storage facilities and battery storage systems in households and businesses across the country – and we need it fast.

About the author

David Roberts is UK Managing Director at GivEnergy – the company empowering energy freedom for all. GivEnergy is the largest British-owned manufacturer of residential and commercial battery storage systems. As well as batteries, the company’s range also includes inverters, EV chargers, energy management software, and a host of supporting accessories. Together, these products create an ecosystem for customers to control their energy end-to-end.

Last year saw significant growth of solar power projects in the UK, despite a temporary setback when major solar initiatives nearly came a cropper due to opposition by a short-lived Prime Minister. Solar Energy UK Senior Communications Adviser Gareth Simkins sets the picture.

2022 was a big year for the British solar industry. Growth was unprecedented and the largest projects yet were announced, while concerted efforts to derail the sector hit the buffers. The UK parliament opened its first inquiry into the sector, although the year ended on a sour note with confirmation of a windfall tax.

The UK now has an estimated 15.5 GW of solar power capacity, having installed about 1 GW last year – a record since the end of subsidies in April2019. By far the largest segment of the solar power market is ground-mounted, accounting for about two thirds of capacity. The rest is split between commercial-scale and residential rooftops.

Why ‘estimated’? Truth be told, no one knows exactly how much solar power is connected to the grid at any one time, due in part to its rapid growth and the lack of any legal requirement to register smaller-scale installations.

Demand for photovoltaic (PV) panels is such that the cost of installation rose for the first time ever last summer, albeit only by a little. Nevertheless, investors are flocking to the sector, attracted by the promise of reliable, long-term returns by solar farms, while the benefits of domestic solar systems speak for themselves. The reasons for growth have changed over the years. The industry was once fed by the enticement of feed-in tariffs and renewable obligation certificates, on top of corporate social responsibility and green-minded desires to decarbonise homes. Now, cost saving is more in the driving seat. Given the massive energy price crisis, it makes sense to turn to one of the cheapest and greenest sources of power available. UK government policies such as the aim to decommission fossil-fuelled generation by 2035 and re-opening the contracts for difference (CfD) regime to solar are also helping to push the sector upwards.

Alongside economies of scale, those are some of the drivers behind projects such as the Blenheim Estate’s Botley West Solar Farm, near Oxford. With a proposed capacity of 840 MW, it is the largest solar project in the pipeline – a dozen times larger than the UK’s biggest existing solar farm.

The enormity of current gas and power bills have made payback periods for domestic solar far shorter. According to a recent report from Solar Energy UK, The Value of Solar Heat, for a typical gas-heated home, installing solar PV panels could save £1,276 a year, implying a payback period of less than six years. Switching from gas to a modern heat pump could save even more.

The figures for new homes are just as stark. Lifetime savings for a detached house in southern England with south-facing solar PV panels, a solar thermal system and a battery storage unit would be expected to exceed £200,000. Even for a home in a sub-optimal location such as north-east Scotland facing east-west, this kind of setup would still save around £3,000 a year.

Despite the largely positive business environment, the current installation rate will have to more than quadruple (4.5 times on average) to meet the UK government’s goal of reaching 70 GW of capacity by 2035. Solar Energy UK has a mid-term aspiration of reaching 40 GW by 2030. Although those goals may look a stretch, a brief glance at the rest of Europe indicates otherwise. Germany installed 7.9 GW last year, taking it to 68.5GW.
Solar Power Europe reckons the nation will hit 131 GW by 2026. Meanwhile, Ireland’s capacity is expected to almost double every year over the next few years.

Key challenges to solar power
So, what is getting in the way here? Figures in the industry repeatedly cite three factors:

• Access to the grid.
• Lack of qualified installers.
• Limited availability of equipment.

Perhaps the biggest bugbear is grid connectivity – a problem faced by solar farms and commercial-scale rooftops alike. A chronic failure to invest in the grid has resulted in waiting periods of up to 15 years. It is common for developers to be told that connections will be available in the first half of the 2030s – stalling net zero efforts and making power pricier.

In December 2022, six energy trade bodies, including Solar Energy UK, wrote to the UK government to demand urgent action to address these constraints, seeking ‘personal leadership’ from Business Secretary Grant Shapps.

Earlier in the year, the UK Warehousing Association (UKWA) slammed the system of distribution network operators (DNOs) – the middlemen between the high-voltage national grid and consumers – as “extortionate and highly ineffective monopolist gatekeepers” that are preventing vast amounts of solar power being added to the grid. The sector is considered to have the potential to double the UK’s current installed capacity.
Out of sight, easy to maintain and affordable, the case for solar should be obvious and yet we are being held back by poor market practice and failures of regulation,” complained UKWA Chief Executive Clare Bottle.

“It’s a tremendous frustration for solar installers and investors alike. So many developments are ready to go, with the potential to slash billions of pounds off energy bills, but are being subjected to huge delays,’ adds Chris Hewett, Chief Executive of Solar Energy UK. “As we are now firmly in the era of expensive gas, energy regulator Ofgem’s drive to keep bills low has had the perverse effect of keeping bills high.”

Solar Energy UK is working on answering the acute demand for labour. Working with the Mayor of London, industry certification body MCS and Community Energy London, the Solar Skills London project is engaging local authorities, schools, colleges and training providers to encourage young people into solar careers. It includes a series of introductory two-week courses and six-week ‘bootcamps’.

As China has now abandoned its post-COVID lockdown policies, access to solar kit should be much less of a problem in 2023 – although the industry recognises human rights concerns in the supply chain. Other countries and regions, including Europe and the US, are ramping up solar production.

Promoting responsible behaviour across the sector was a theme for 2022,with the launch of the Solar Stewardship Initiative (SSI). Backed by SolarPower Europe and Solar Energy UK, the SSI seeks to guarantee adherence to environmental, labour rights and ethics obligations, and trace products along the entire supply chain, back to raw materials. The initiative is based on standards from the United Nations, ISO, World Resource Institute and OECD.

A further element is boosting biodiversity. Contrary to some ‘ill-informed’ claims, there is mounting evidence that solar farms benefit nature – under investigation in a project sponsored by Solar Energy UK. The association has also published best practice guidance on monitoring biodiversity and detailed advice on how to increase it and integrate solar farms with agriculture.

The latter issue provoked the low point of last year, when Liz Truss dismissed solar farms as ‘paraphernalia’ in a prime ministerial hustings speech. It came amid increasingly organised opposition to solar farms, with groups making false and exaggerated claims about landscape impacts and that solar farms threaten the food supply. In fact, the opposite is true. Solar farms benefit food security by addressing climate change, which the government acknowledges is the number one threat to British agriculture. They also help keep farms in business by cutting energy expenditure.

A temporary low point
During his brief tenure in office, Truss’ Environment Secretary Ranil Jayawardena proposed extending planning restrictions for good quality farmland to middling ‘3b’ land. As the worst grades tend to be in upland areas, distant from the grid, virtually all current solar farms are on 3b land. This initiative would have amounted to a de-facto ban, risking £20bn of investment, destroying jobs and doing profound harm to net zero efforts –and all amid the worst energy crisis for a generation.

Friends from across the political spectrum rallied against the prospect: the Conservative Environment Network, the Green Alliance and the Labour front bench, to name a few. Shadow Climate Secretary Ed Miliband responded with a promise to treble solar generation within the party’s first term if it wins the next election. ‘This government cannot deliver when you have a Prime Minister who is a longstanding opponent of solar, and an environment secretary doing her bidding,’ he told The Guardian last October. Rishi Sunak’s administration has since confirmed that the threat is over and has offered a much more positive view of the solar sector. But a thorn remains in the industry’s side: the unfair 45% windfall tax. Given that most large-scale solar projects are ‘merchant’ schemes without the protection of a CfD, it could well hit investment just when it is needed most. Renewable generators will also be unable to offset the tax with new investment, unlike the oil and gas sector.

‘The government is tilting the playing field against renewables investment, while having told the world at COP27 that we want to be a clean energy superpower. The policy simply has to match the rhetoric,’ said Hewett.

This blog was originally published in New Energy World on January 2023.

Author: Gareth Simkins – gsimkins@solarenergyuk.org

21 July 2021:

Solar technology has been in the vanguard of the UK’s shift towards a decarbonised, decentralised energy system for years. Photovoltaic panels are an immediately recognisable indicator that a household has made the first big step to greener living, and the rooftops of the UK have been changed forever. Those panels are now found on one in every 25 buildings. 

We have proved to be a nation of solar enthusiasts, but the job is very far from done. There is still an enormous, untapped opportunity for even more solar-powered renewable energy generation in this country.

In many ways there is an obligation too. The built environment contributes a staggering 40% of the UK’s carbon emissions. Unless we can heat and power all our buildings – homes, offices, schools and hospitals – in a radically different way, the government’s target of reaching net zero carbon by 2050 will prove completely undeliverable. 

But at the Active Building Centre, we believe we can be even more ambitious, and look beyond a zero-emission goal for the UK’s housing stock. Let’s have homes that are no longer a liability on the national emissions balance sheet, but are assets instead.

Unsurprisingly, solar will again have a crucial role to play in this next stage of the energy transition. The industry already promotes battery storage and smart systems that manage and optimise energy consumption, working alongside those photovoltaic cells. This matches our vision of how the best future homes will look: ultra-flexible, energy-efficient buildings with electrified heating, electric vehicle charging points and battery storage, all integrated into an intelligent system. We call those Active buildings, and they will be an important part of all our futures. Indeed, they will set the very standard for all our future homes. 

Importantly, however, an Active home also has the ability to redistribute energy back into the grid, depending on the smart system calculating when is best to store surplus energy and when is best to sell it. This earns a return for the homeowner and, applied on a national scale, converts the UK’s housing stock into a network of millions of decentralised renewable power stations. Excitingly, those personal power stations can come in many forms – wind and hydrogen can play their roles – but solar will be a critical part of this energy mix.

Solar is an exemplar of how many of the technologies that will power Active homes are already proven and available off the shelf. Others, like the new generation of heat pumps that our engineers are working on, will continue to be refined and upgraded. 

Our job at the Active Building Centre is to show how these different technologies can be affordably and effectively integrated into smart and self-sufficient energy systems. And as Active homes become the norm, the energy make-up of the UK will be radically transformed – with those glorious solar cells dotting even more of our roofs.

21 July 2021:

A core part of Solar Energy UK’s work revolves around talking up policies that would boost the growth of the UK’s solar energy markets. For example, reforming the business rates regime, supporting up-front financing, and addressing reliability myths are three ways in which the deployment of rooftop solar technologies could be accelerated.

Fortunately this is a view that Government researchers share, according to a new public attitudes report published by BEIS earlier this month. The research, which involved 15 small and medium-sized enterprises (SMEs) and nearly 900 households across Great Britain, was aimed at understanding the barriers and enablers to solar PV adoption.

With the UK currently wilting under a heatwave, this timely report highlights factors influencing consumers and businesses in their decision to invest in solar energy technologies. According to the research, measures which might increase deployment on household rooftops include:

• Establishing a scheme to address consumer risks about the reliability of solar panels. This is even though, as the research highlights, solar PV is an extremely reliable technology.
• Raising awareness of schemes such as the Smart Export Guarantee, which provides homeowners with the ability to sell surplus solar power to the national electricity grid.
• Developing new financial mechanisms to spread out the costs of installing a solar system over time.

For businesses, the report, which was based on in-depth interviews with SMEs, highlighted the attractive economics of solar. Respondents suggested that this is a major reason to install a rooftop system, reflecting the findings of Solar Energy UK research on the costs of commercial solar. The research also identified the environmental benefits of installing onsite solar generation as increasingly important for businesses’ reputation, and licence to operate.

However, respondents highlighted regulatory uncertainty as a risk. For the SMEs surveyed, the “single biggest barrier for the adoption of solar” is the potential for increases in business rates. Solar Energy has previously highlighted the impact of the business rates regime, including writing to the Chancellor in 2020, with wide support from across business and industry. Solar Energy UK has produced Business Rates advice for companies to understand how to calculate their liabilities, and continues to call on the government to ensure there is a level playing field for onsite solar power generation.

Overall, the BEIS research corroborates what Solar Energy UK members often cite as solar’s key advantages: it is an affordable, accessible, and effective way to reduce carbon emissions. As the report makes clear, there is also “headroom for expansion” – for example, in London, which has a relatively low deployment footprint at the moment. Solar Energy UK recently launched Solar Skills London to support the expansion of the capital’s solar industry. 

The BEIS report noted the strong growth in UK solar, including since the end of the installation subsidy feed-in tariff, with solar panel installation costs having declined by 60% since 2010. Home occupiers can also make money by selling power to the national grid. Solar Energy UK’s Smart Export Guarantee league table enables consumers to identify the potential revenue that could be earned from the surplus electricity produced by home solar panels.

To learn more about solar PV’s deployment potential around the country, read Solar Energy UK’s flagship report, Lighting the way. This report includes clear recommendations which, if implemented, could see the deployment of 40GW of solar power in the UK by 2030, a level consistent with the UK meeting its climate change target of reaching a net zero economy by 2050.

ENDS

By Ben Milne, Policy Research Assistant and Kevin McCann, Policy Manager.

08 June 2021:

Power Games

The rated power of solar PV panels has climbed steadily over time. This has been driven in large part by innovative new processing techniques for the cells themselves, although improvements to the technology of panel assembly has also played a role. Over the decade from 2010, customers of the panel manufacturers came to expect higher and higher module powers each year.

Because all panels were the same size, the panel power was a good shorthand measure for how advanced the cell technology was. If a panel was rated at 320Wp then it would generate 14% more energy per square metre of space than a 280Wp module.

Squeezing more power (measured in Watt-peak – or Wp per panel) into the same footprint tended to drive down the cost per installed unit of rated power ($/Wp). Since the cost of the glass, frame and other components of the module and all the installation materials remained the same for modules of any power. The inexorable rise in power density of the available cells was a significant factor in helping the industry achieve the amazing feat of cost reductions we have seen over that decade.

In addition, new techniques for squeezing every drop of performance out of the cells in solar modules have also allowed the accumulation of small gains. Using a greater number of conduction wires (bus bars) with a more slender width on the top face of the cells reduces power lost due to shading of the cell below and also reduces losses from electrical resistance. Cutting the cells into halves, or thirds, or quarters and wiring all these fragments together into parallel circuits again reduces resistance losses as well as reducing the sensitivity of the module to shading. The efficiency gap between measuring the cell in isolation compared to the assembled panel has reduced over the years.

However, gains from improving cell powers have reached a plateau. See my blog on why solar cells are not getting more powerful (coming soon).

So manufacturers reaching for new ways to keep the story of ever more powerful modules at ever lower cost per Wp going have found a simple answer – just make the cells and the panels bigger.

Breathless excitement from credulous industry commentators as announcement of modules exceeding 400Wp, then 500Wp barriers misses the point. A not-so sleight of hand is evident as soon as you look at the product behind the headline number. Panels are not getting better, they’re just getting bigger.

You can have any (size), so long as its….
When it came to solar PV panels (modules) we all used to know where we stood. A solar PV panel was just under 1m wide and around 1.65m long. It had each of its 60 cells were 156mm square. A defacto standard for PV panels emerged around 2010 and manufacturers stuck to it.

Using the Waybackmachine internet archive I accessed historic web pages of industry stalwart Trina Solar. For each year where I could find the information, I downloaded product information for the highest power module that was being offered for sale at that time. See the graphic at the top of the page.

You can see that from 2009 to 2018, its module powers increased from 230Wp to 315Wp while their size remained the same. The corresponding module power density increased from 141 to 192Wp/m2.

Today Trina Solar offers modules with powers ranging from 320Wp to 600Wp by virtue of offering modules of much larger dimensions.

There were many advantages that came from working to a standard size.

In manufacturing – everything from the sheets of glass to the width of the encapsulant film and backing sheet to the pallets and packaging could all be made to the same size. Economies of scale for the whole industry drove down costs and raw materials are readily available from many different suppliers.

Downstream, manufacturers of so-called ‘balance of materials’ equipment could also standardise their products.

The electrical characteristics of the modules were all in a relatively small range and manufacturers of module level power electronics (MLPE) such as power optimisers and microinverters could easily cover the whole market with a small range of products.

Since the physical dimensions of modules varied so little between models, manufacturers of roof mounting kits also benefitted. The wind loading per module was the same for all modules, allowing optimised designs for fixings. The spacing of point loads on rails was consistent for any design. Roof integrated BIPV products emerged that worked with these standardised modules and relied on their predictable format for wide interoperability and a single wind resistance value (though fire classifications proved less simple).

When designing with standard sized modules, solar installers had confidence that the system they were designing would be available both now and into the future. This is especially important for new build projects where the design may be priced for construction many months or even years in the future. Even if the specific module selected with was no longer available, an alternative of the same dimensions could easily be found.

Finally customers benefitted from the knowledge that in the event that a single panel in a system was to fail, that a replacement of the same format would be available in future and could simply drop into the mounting system.

Battle of the Formats

A standards war has broken out with TrinaSolar, Risen Energy, Canadian Solar and others lining up against Hanwha Q Cells, REC Group, LG on the one hand and Longi, Jinko and others on the other – each calling for the industry to focus on cells of the dimensions they prefer. Will the industry settle on 158.75, 166, 182, or 210mm? At this point nobody knows.

(See my guide to different PV cell size formats here)

In any case the cell size no longer quite defines the module size. Since manufacturers have started slicing up cells into smaller sub-units (half-cut , third cut cells) there is greater freedom to choose different module sizes. Dizzy with this new found freedom, module designers are expressing their creativity with the results of a a wide range of module sizes now available in the market (see graphic).

Even within single manufacturers a range of many different panel sizes are now on offer. The graphic shows a sample of products available from four of the larger industry players. Panel powers range from 320Wp to 800Wp, but as can be seen the power density (Wp/m2) ranges only from 193 to 212 Wp/m2.

This is because the cells are pretty much the same but the packing efficiency is ever so slightly higher in a larger panel (because the edges are a smaller proportion of the whole).

An arms race for ‘plus-sized’ size panels is in progress, with JA currently in the lead offering the Jumbo Blue at 2.2m x 1.8m and 800Wp. These panels are completely impractical for rooftop applications, but are aimed instead at utility scale ground mount.

It seems that module manufacturers have decided that the cost and convenience benefits of standardisation of module sizes can go hang. Instead they are pursuing a product strategy of scaling up panel dimensions to increase panel power that is leaving the rest of the solar supply chain scrambling to catch up.

Where will this end? There are clearly practical limits. How big a module can customers handle? The answer to this question depends on where you are trying to install it. If you’re on top of a windy roof you don’t want to be humping round a 4m2 monster, but maybe that’s perfectly fine with mechanised lifting for a ground mount system.

The economics of solar PV has changed. Modules now dominate the cost structure of a solar PV installation to a much lesser extent. While it was the case that the module was the principal cost, it made sense to work with a standard format and drive out as much cost as possible. As panel prices have fallen, maybe it does make sense to design specialist modules for different jobs. Naturally manufacturers are focussing on their most important markets – solar farms and hence the rush to produce the bigger formats, which reduce other costs in installation and clamps.

Could this trend extend beyond different panel sizes to panels with special design features for different applications? Maybe in future the panels used for flat roofing installations will be different from those used for fixing to corrugated metal roofs and have special features that make installation easier? Or maybe the industry will step back from format wars and settle on a few standardised sizes for different applications. Some folks in the business of making mounting kits for the solar modules made by these manufacturers must certainly be hoping so!

07 May 2021:

The hardest part of writing a blog – finding a title that will draw in the audience.

NextEnergy and partners are proud to have developed and constructed a 75MW solar site called Llanwern in South Wales. I first heard of the Llanwern project in late 2017; it was expressed as a site covering many full-sized football pitches, certainly much larger than any site that NE owned to date. In fact, at the moment, it is the largest solar site in the UK, a site covering 145 hectares.

Then in March 2018 the project secured its Grid and planning rights.

The location was described as close to Newport, then I did a little more research and realised that the area was in fact part of the Gwent Levels; an area classified as a site of special scientific interest (SSSI).

It has been noted that it was in use 5000 BC, however, it was reclaimed back by the sea. A Roman General Sextus Julius Frontius, based at Caerleon, built a sea wall and reclaimed the land behind the wall. Ditches (known locally as reens) were developed so that water from the uplands could reach the sea without flooding the reclaimed land. It was in use for 350 years by the Romans. After their departure, the monks at the Goldcliff Priory took on the task to master the land. In 1530, King Henry VIII, created the Courts of Sewers and the Courts of Caldicot and Wentlooge were established. This was a formal undertaking to ensure that the land was managed properly. No financial support was given by Royalty or Government, however, it was left to the landowners and they were policed by the Courts of Sewers, in Llanwern it was the Court of Caldicot.

To gain planning permission, numerous studies that had to be undertaken, archaeological to ecological to name but a few, to satisfy an understandable number of interested parties.

The area is sometimes referred to as the living levels, as the site has reens; amphibians will have shared use. Along with invertebrates, reptiles, badgers, bats, lapwings, common cranes, rare bumble bees (the shrill carder bee), dormice, brown hares, and hedgehogs; along with others not singled out with a mention. The hedgerows and field boundaries include mature willow, oak, ash and horse chestnut.

The development team worked with specialists to ensure that nothing could or would be overlooked for its future management as a solar plant. Much research was required to gain a full understanding and appreciation of the land management requirements during its development, construction and full operation.

A Construction Environmental Management Plan (CEMP) had to be developed and approved. The plan during pre-construction, led by an ecologist to ensure that habitats, hedgerows, trees, bats, water voles, ground nesting birds and nesting birds (trees and hedges) were left unscathed.

For the next 40 years NE will be the custodians of this beautiful part of Wales, with its reed-fringed ditches, maintained in line with a 44-page Landscape and Ecology Management Plan (LEMP).

Wildlife features added in the form of bird boxes of varying sizes and entrance holes to suit different species, tree sparrow boxes, barn owl boxes, and bat boxes. Habitat piles to benefit reptiles, invertebrates and amphibians, will be constructed from arising from the hedgerows and placed in corners of fields. Bug hotels constructed from suitable materials of the site infrastructure.

This estuarine landscape, a patchwork of fields edged by reens and sluice gates to manage the flow of water, has contrasting seasons which attracts migrating birds.

A seasonal visitor is the Common Crane, and dedicated areas of habitat have set been set aside for them to continue their use of the land. Crane crossings have been added, timber planks crossings to allow cranes with chicks to move between fields easily. Water quality was to be maintained throughout construction and will be through the duration of the solar farm’s operation. It will be an interesting solar site to observe, and certainly an area worth a visit.

Members, to find out more on the biodiversity benefits of solar, please join our next Natural Capital Working Group, to RSPV click here.

06 April 2021:

Solar Energy UK would like to wish our members a happy Easter and extend a message of thanks for your continued support throughout the year.

Spring is a time to celebrate new growth and honour the natural rhythms of the earth. As the evenings are drawing longer, and solar’s share of the electricity mix increases, it seems appropriate to remind ourselves that solar farms are the most nature-friendly way of generating power for the grid. A well-managed solar farm is teeming with biodiversity benefits, whether by allowing livestock to continue grazing, permitting small animals access to otherwise fenced-off land or bird and insect fodder plants and wildflowers sown around the modules.

To showcase the many contributions from our membership towards supporting biodiversity, Solar Energy UK is once again calling for members to submit their best photographs! These photos highlight the excellent work taking place across the industry, and support the Association to continue producing visually stunning content that shine a light on solar in the UK.

Entries are requested for the following categories:

• Solar Roofs
• Solar Parks
• Biodiversity
• Energy Storage and Emerging Technology

The winning entries will have their photos displayed at our exhibition stand at Solar and Storage Live. To enter please send your photos to Kara Davies (via email or WeTransfer). When applying please specify company name, competition category, location and type of installation, along with any other supplementary information. Please note that all photos must have been taken in the UK, in 2020. 

The extended deadline for entries is Friday 30 April at 17:00 GMT.

22 February 2021:

We spoke to Stefan Kintscher, General Manager for the Value Chain Integration Group at Hitachi, and Helen Grundy, Environmental Specialist at Hitachi, to see how they are approaching their journey to a more sustainable future. What became clear very quickly is that the company has been aware of its responsibility to help tackle climate change for some time and has, on a global scale, been increasingly focused on how it can achieve its ambitious decarbonisation targets.

Helen: “At the beginning of our current mid-term management cycle, we announced our aim of carbon neutrality throughout the business by 2030. Since then, a significant amount of time and resources have been dedicated to making this a reality. We started by using energy more efficiently, then generating renewable energy, procuring it and offsetting our carbon footprint. The enhanced efficiency of procuring sustainable energy as a group, rather than as separate businesses, is being realised. The company has always designed products that add value to people and the planet – we are now ready to take this one step further.”

Despite the growing enthusiasm and opportunity for increased energy sustainability, the transition to renewable energy sources is not without its challenges.

Stefan: “The first major challenge is the technology itself – there is a variety of options available and they are changing rapidly. Determining the best tech for different sites and for the business overall can be complex. The second greatest challenge is the cost. There is a lot of excitement and momentum among many business sectors to go carbon-free, but achieving this while remaining competitive is difficult. A balance must be found between adequate investment in renewable energy sources and still maintaining healthy project margins to prevent other areas of the business from suffering. At Hitachi, we use our scale, size and capabilities to offer world-class technology solutions while remaining highly competitive.

“As industry moves forward, it will be very interesting to see how all businesses fair in the journey to decarbonisation. Smaller companies often carry a lot of the innovation, but some may struggle to make the transition due to lack of capital or resources. We are using extensive internal teams to navigate the renewable energy procurement process – those without access to similar resources will need to find innovative ways to master the challenges. As such, I don’t believe that size alone will dictate success in the sustainable energy field. It’s about finding smart solutions that suit the individual business.”

Stefan and Helen point out that there are a huge number of aspects to consider when seeking renewable energy sources and each company will have unique constraints and opportunities. In order to overcome the issues and maximise on the benefits, they agree there is a profound need to simplify the procurement process, as this will increase accessibility to businesses of all shapes and sizes around the globe. Discussing other areas in which renewable energy suppliers or generators could support businesses in their decarbonisation targets,

Helen: “From an environmental and sustainability perspective, we need access to clear, robust reporting. This allows us to collate the data needed to manage and report on our energy use effectively.”

Stefan: “At Hitachi, we are very interested in working with the best of the best in each market. We get to know the energy suppliers or generators we’re interested in working with, exploring their energy procurement processes, investment in renewable tech, network solutions, charging vehicles and PPA solutions, including virtual PPAs, in addition to their reporting tools. Our aim is to choose the best fit for our ethos and company to help us achieve our carbon goal while staying as competitive as possible.”

Stefan will be presenting at the first Clean Energy Exchange 2021 webinar of the year, on 23 February. He will share the learnings of Hitachi’s journey to decarbonisation so far, highlighting the difficulties of the transition even for a global business like Hitachi with significant resources and incentives. He will also outline his search for strong and capable partners in the sustainable energy sector to potentially work with going forward. If this could be you, you can contact Stefan here.

Clean Energy Exchange 2021 is a webinar series produced by Solar Energy UK and Renewable UK. The first virtual event in the series will focus on the growth of clean energy in the technology sector, offering fresh insights into how technology companies are procuring renewable energy and investing in the green power infrastructure of the future. More information available here.

The energy landscape, like many other things, has changed dramatically since the turn of the century. When the last Energy White Paper was published, in 2007, coal served as the backbone of the grid, meeting 43% of UK electricity demand at a peak in 2012. Fast-forward seven years later and this has shrunk to little over 2%. Solar PV has gone from adorning the roofs of a few early adopters to more than one million installations across residential and commercial sites, and well over 1000 large-scale ground-mounted parks.

Globally, solar has been crowned the new energy king. This is bolstered by the emergence of, battery storage and electric vehicles as consumer mainstays, and commitments to achieving rapid decarbonisation being at the core of many business strategies across the industrial spectrum.

The Government’s new Energy White Paper has been anticipated for a couple of years now, its publication no doubt hindered by the uncertainty brought about by Brexit and, more recently, COVID-19. Many have bemoaned the continued delay, but this paper holds the potential to deliver a fundamental shift towards net zero, and as such we can afford to wait just a little longer. No stone should be left unturned as this Government seeks to drive policies which will produce a green economic recovery.

Solar’s role in this must not be overlooked. As a decentralised technology it provides high quality jobs from Land’s End to John O’Groats, and by the Government’s own reckoning is set to be the cheapest source of power for years to come. It becomes a no-brainer when you add this to its long lifespan, abundant popularity with the public, and its potential to support thriving ecosystems and biodiversity.

Indeed, the STA estimates that with moderate policy intervention in areas such as building standards and business taxation we could see upwards of 5,000 more jobs created annually in the solar and energy storage industries, and a boost of almost £1billion to GDP. These are not trivial figures – the solar industry has shown remarkable resilience to the Coronavirus crisis and stands ready to help deliver a rapid green recovery.

The White Paper should serve as an indicator of the UK’s net zero ambition for solar, batteries, renewable hydrogen and beyond, laying the foundations for a more holistic and ambitious approach to deliver low carbon energy. It is important that this Government’s aspiration for levelling up the deployment of renewable technologies is made clear, as well as how it intends to deliver the commensurate investments in infrastructure needed to support this, such as reinforcement of the grid.

The Government has already made its intentions around one particular renewable technology apparent, with a commitment to reaching 40GW of offshore wind by 2030. It must do the same for others that will serve as a significant part of the energy mix in the coming decades – especially solar PV, onshore wind, and battery storage.

Demand for these technologies is no longer being driven solely by policy, but is coming direct from large energy consumers. Major retailers such as Tesco and Amazon are investing millions, as are utility companies and local authorities. The Government’s role in driving uptake is now one that must facilitate the market by bringing down barriers, whether fiscal, regulatory or based on practicalities such as addressing skills shortages. An explicit target would act as the starter gun to refocus policy priorities.

For solar PV, any government target must be in line with the expert analysis of the Committee on Climate Change, which states that 54GW needs to be deployed by 2035 to remain on track for net zero and the UK’s carbon budgets. This equates to delivering 40GW of solar in the next decade, an ambitious yet entirely achievable figure that will help to focus policymaker’s minds and drive confidence across the industry that this Government recognises the real potential of solar energy in the UK.

With the world watching as COP26 looms on the horizon, and the time available to limit global warming to 1.5oC ticking away, it is incumbent on this Government to lead the way and deliver a comprehensive strategy that unleashes the true economic and ecological potential of renewable energy in the UK. Anything less will not be good enough.

Earlier in the Autumn the Government announced a £2bn package for a grants scheme to drive retrofitting in homes across the country to reduce carbon emissions. It generated great headlines, warm words from the environment movement and provided a tangible example of how the country might ‘build back better’. Hooray for the Green Homes Grant you might think.

Sadly, the delivery of the scheme has yet to match the rhetoric.  Yes, I know that sounds all too familiar right now. What is currently on offer has many flaws and unless the scheme changes significantly it will, at best, deliver a tiny proportion of what Ministers claimed and, at worst, pay for poor quality work, encourage mis-selling and actually damage the reputation of the existing retrofitting industry.

The solar energy industry is currently only partially impacted. Whilst solar thermal installations are eligible for a Green Homes Grant voucher, solar power and energy storage installations are not. Initially this seemed like a huge missed opportunity for the industry, but frankly under the current scheme rules, we have dodged a bullet. I suspect most STA members will not engage with the scheme at all until it has been improved.

Last week MCS Chief Executive, Ian Rippin, criticised the scheme as being ‘pushed through at breakneck speed without being properly glued together’, and we have also been hearing similar feedback direct from our solar thermal installers. Martin Lewis of Money Saving Expert has called it a shambles. The main flaw is the requirement for the entire £2bn budget to be spent by 31 March 2021, after which there is nothing. Add to that the delay in release of the vouchers until November 2020 at the earliest, and the lack of resources available within the scheme administrators, and it is obvious that the scheme is undeliverable.

The MCS Helpline is handing a huge influx of customer enquiries, because they have people on the end of a phone, where other organisations haven’t had the chance to scale up. Installers themselves don’t have the resources to handle such an increase in inquiries which all need home visits, quotes and a lot of hand holding of customers, coupled with a real uncertainty about how the work will actually get paid for (see confusion on vouchers above).

Rest assured we have fed all of this back to the Government, as have many others. Officials are doing their best to improve the system, but until the Treasury extend the deadline for the scheme by 18 months at a minimum, the Green Homes Grant will be unfit for purpose.

The answers to the challenges are very clear. The existing £2bn Green Homes Grant budget should be available to spend until the end of 2022 and eligibility should be opened up to all zero carbon retrofitting options, including solar PV and energy storage. This would allow installers to invest in their workforce and create jobs, maximise the number of potential householders who might be attracted by the grant scheme and use the skills and resources of the best quality assurance scheme for zero-carbon retrofitting – MCS.

Once these no brainer changes are put in place there should be a proper consultation with industry on designing a long term scheme for retrofitting homes in line with net zero, out to 2030. This should integrate government grants with incentives for green mortgages, rolling out smart metering, EV charging and Ofgem regulation on network upgrading.

To avoid the worst of climate change there must be a rapid shift to clean energy. In tandem with efforts to reduce emissions from highly polluting coal and gas power stations, the UK is also tasked with restoring and supporting healthy ecosystems across the country to tackle a growing biodiversity crisis.

Large-scale PV technology can play an instrumental role in tackling both of these challenges, driving the UK’s shift to a zero-carbon economy while simultaneously enhancing natural capital.

Although it is challenging to measure on a global scale, in recent years many countries have reported a consistent decline in biodiversity. In 2018 the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) reported that the UK was experiencing a decline in the abundance of priority species. Covering a range of aquatic and terrestrial flora and fauna, statistics indicate that both the distribution and richness of many UK species has been in spiralling decline since 1970.[1] According to DEFRA, 40% of England’s habitats and 30% of priority species are still in decline.[2]

Britain’s solar industry is stepping up to the challenge. Experts from across industry and academia have worked together to develop tools that further enable solar projects to enhance the local environment, while continuing to generate an abundance of clean, low-cost power.

One example of this is the Solar Park Impacts on Ecosystem Services (SPIES) tool, which summarises the best available evidence of the impacts of a range of land management techniques on ecosystem services at each site. SPIES brings together evidence from over 450 academic articles, specifically tailored to UK environments, and it allows users to filter evidence by desired ecosystem service, which then generates a list of tailored environmental management opportunities. Furthermore, users of the tool can qualify and, in most cases, quantify the value of ecosystem services at current solar parks and those in the planning pipeline, ensuring each site can maximise its promotion of biodiversity. [3]

In comparison with other energy generation technologies, ground-mounted solar has a significantly lower environmental impact overall, and can be successfully coupled with agriculture, aquaculture, and the built environment. Solar parks are temporary structures with an average life span of 25-40 years. They are secure sites, requiring little human disturbance, and with an infrastructure footprint typically covering less than 5% of the total area of a site. Where sited in an agricultural setting, they also offer a valuable fallow period for land that has been intensively farmed, allowing for the restoration of healthy, fertile soils.

Solar Energy UK’s Natural Capital Value of Solar Report published in 2019, provides clear evidence that solar parks which are well designed, constructed and maintained properly can have a net positive impact on the natural capital value of the land and support a wide range of ancillary ecosystem services.

One of the unique advantages to solar parks is the very minimal disturbance from humans or machinery after installation, which maximises habitat potential for a range of wildlife.[4] This synergy between PV and the natural world can be further enhanced through the creation of a range of different habitats including hedgerows, ponds, and wildflower meadows. Each solar site differs from the next, offering unique opportunities to optimise habitat value.

Drainage and on-site water management are also key considerations when planning a solar development. On any solar site, surface water must be adequately managed by implementing open draining structures such as swales or balancing ponds instead of sub-surface drainage. Solar parks will often feature a stable water management system, providing rich wetland habitations, which are in steep decline.

While solar park developers are always required to consider the environment in planning, many now are seeking ways to maximise the biodiversity contribution their projects can make. One recent example in the UK, is Britain’s most advanced park built by Gridserve in York The park consists of 90,000 bifacial panels, meaning they are able to harvest sunlight on both sides of the panel, increasing the amount of light captured. Bifacial panels by nature are more light-permeable and promote growth of wildflower species underneath the panels. But what really makes this site particularly special is the species of pollinating plants Gridserve have chosen to use. The exact species remains a company secret, however the science behind it hints that planting this reflective variety underneath the bifacial panels could promote a “boost” in solar performance.

Another exciting prospect is the Cleve Hill Solar Park, set to be sited in North Kent. The project is set to deliver a net biodiversity benefit of 65% owing to features such as a dedicated Habitat Management Area the size of 138 football pitches which will provide a home for a range of bird species including Lapwing, Brent Goose, Golden Plover and Marsh Harrier. Less than half of the total site area will be adorned with panels, with plans for a large open meadow area, likely to be one of the largest in South East England, in addition to woodland, hedgerows and grassland, providing habitat for a variety of wildlife.

With solar sites offering some of the best opportunities to deliver a vital boost to biodiversity in Britain, project developers are taking their responsibility as stewards of the land seriously. As this progresses, solar parks will increasingly become vital wildlife havens, serving the environment in ways that most other technologies cannot.

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[1] https://nbn.org.uk/wp-content/uploads/2019/09/State-of-Nature-2019-UK-full-report.pdf

[2] https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/69446/pb13583-biodiversity-strategy-2020-111111.pdf

[3] https://www.lancaster.ac.uk/news/articles/2016/spies-tool-aims-to-support-solar-park-developments/

[4] https://www.solar-trade.org.uk/wp-content/uploads/2019/06/The-Natural-Capital-Value-of-Solar.pdf