University of Surrey                            OSE0027

Written evidence from the University of Surrey Advanced Technology Institute

Introduction

The University of Surrey’s Advanced Technology Institute brings together researchers with specialisms in quantum information, nanotechnology, energy and advanced materials.

The Institute and its members work on cross-cutting themes, addressing the “grand challenges” in energy, healthcare, information technology, sustainable technology, and more generally, technologies associated with “quality of life”.

This response has been prepared by Professor Ravi Silva, Director of the Advanced Technology Institute and Head of the University’s Nanoelectronics Centre. Professor Silva would be pleased to support the Committee further in its inquiry and can be available to provide oral evidence once sessions are scheduled. 

Further information about the Institute and its research is available here.

What role can developments in solar panel technology play in the UK’s transition to net zero?

In order to achieve the carbon net zero target highlighted by the 2021 International Energy Agency (IEA) Report[1], the IPCC stated that we need to decrease our methane emissions from fossil fuels by 75% over the next 10 years, while maintaining a world economic growth of 40%[2]. Moreover, we will need an additional 1000 GW of wind and solar energy by 2030, meaning a target of 100 GW per annum is required in the ratio of 60:40 solar to wind[3].

The IEA’s World Energy Outlook[4] states that solar photovoltaics (PV) or wind “represents the cheapest available source of new electricity generation.” The report goes on to say that “the low costs of wind and solar PV mean that more than half of the additional emissions reductions could be gained at no cost to electricity consumers.” This is observed in real terms with the large number of power purchase agreements (PPA) being signed in the current climate of potential energy brownouts in early 2023.

The Department for Business Energy and Industrial Strategy (BEIS) has produced estimates for the levelized cost of electricity (LCOE) of different technologies in the UK since 2010[5]. Solar PV is now cheaper than nuclear, combined cycle gas turbines (CCGT) with and without carbon capture and storage, and offshore wind[6].

BEIS LCOE estimates over time, showing large-scale solar being the cheapest form of new build electricity at scale in the United Kingdom.

BEIS suggests that future solar technology will only require 2 to 4 acres of land, compared to the current amount of 4 to 5 acres[7]. To achieve the goal of 5-folds of 70GW, taking an average of 3 acres per MW will require 700 square kilometres of land which is equivalent to less than 0.3% of UK’s overall land area[8].  This is broken down in detail below:

• Fivefold of solar energy target (14.6 * 5) = 70GW
• Ground mounting system (65%) = 45GW 3 acres = 1.214 ha
• 45GW (45000MW * 1.214 ha) = 54000 ha
• 54000 ha is 0.22% of 24.3-million-hectare acres.
• Therefore, overall area will require less than 0.25% of total area of the UK.

After the solar incentives, capacity rocketed from 5GW to 14.6GW. To put this into context, none of the 71% of total UK land designated as agricultural land suitable for irrigation (17.3 million hectares) needs to be touched. In terms of current use, the required land to hit the modest 2035 increase would most likely be less than either the land occupied currently by mostly unused mines, or the equivalent land used by airports.

As nuclear energy is much more expensive and will take many years to construct (on average 5-10 years), renewable energy technologies like solar power and wind power must increase considerably. With the lower cost of deployment, and lower cost for consumers, it is purely the difficulties in planning permission that is delaying large scale deployment on a commercial basis in the UK. 

What are the current barriers (regulatory, technological or otherwise) to expanding the number of small and large-scale solar installations in the UK?

For any small-scale installation (>9 sq. m) the planning system can be restrictive. When the scale is beyond a modest value suited for commercial purposes, rigorous environmental, ecological, and socioeconomic planning, it can take months or years to satisfy local authorities. This can act as a barrier to commercial take up even on a domestic scale, with planning permission often refused for minute interventions.

If the UK is to fully realise the potential of onshore solar power generation, there needs to be a review of the planning policies for modest scale solar installations in the UK to ensure that these support the UK’s net-zero targets. This will help to provide guidance and clarity to local authorities who are responsible for smaller installations, who often lack the strategic support for such developments.

Grid connection can also be a barrier where long lead in times make investment and commercial use less appealing.

A clear regulatory and policy environment will be critical in ensuring steady investment into the UK’s solar sector and provide much-needed certainty for planning authorities who are ultimately the decision makers for a large proportion of installations.

To what extent is the contribution of solar technologies to the UK’s renewable energy mix limited by storage and distribution capacity?

Many emerging technologies tackling the issue of sustainability and energy usage are heavily dependent on technology advancement in battery storage technology. The size, scale, and distribution of the innovations required in solar energy harvesting and energy storage are unprecedented. The current technologies may be sustainable for the next ten years, but it will not be viable beyond that.

New solar materials are needed that are much cheaper, more easily deployed, with shorter payback times, and increased stability, maintaining the 20–30% efficiencies currently available with the incumbent silicon solar technology[9].

For a future energy mix to be supplied in the most part by renewable green energy sources, a suitable local smart grid, with regional local energy storage means needs to be encouraged. This will not only release pent up potential of new inexpensive energy source use but also help to facilitate regional manufacture; where in large cities electrical energy is at a premium due to substations operating at their safety limits due to demand from the public and private sector enterprises[10].

On average, new large businesses need to support very large electricity supply costs to network providers due to the short fall of capacity. Therefore, the provision of large-scale electricity farms not only allows for the pent-up release of additional energy for SME and manufacture, but it also allows support of novel regional energy storage routes.

How significant are current technological developments in energy storage and distribution networks for the potential contribution of onshore solar to the UK’s renewable energy mix?

The dominant form of electrical energy storage today is pumped hydro. However, suitable locations where two reservoirs can be constructed nearby at significantly different altitudes are rare in the UK[11]. The National Grid[12] expects pumped hydro to increase by around 25% from approximately 4 GW in 2030 to 5 GW in 2050 according to its Consumer Transformation model, which assumes the 2050 net zero target is met.

Furthermore, the pumped hydro will be used more often and as such the energy stored will almost triple from approximately 30–80 GWh over the same period. Other forms of energy storage will also need to be established over time. Additionally, hydrogen could become an important means of energy storage.

The National Grid’s forecasts also suggest that the dominant energy storage technology in 2050 will be vehicle-to-grid (V2G). This uses the batteries of electric vehicles for short-term energy storage (while the vehicles are not in use). The Vehicle to Grid Britain[13] study found that by 2040, V2G storage capacity in the United Kingdom could reach 180 GWh - around 12% of projected daily electricity demand in that year. Further new storage routes at local and regional level will encourage large vehicle fleet operators and regional railways to provide suitable energy storage that potentially can be locally mobile with suitable caveats for the variations available due to limited movements.

However, in terms of power capacity, the main storage technology by 2050 will be dedicated batteries[14]. The nascent field of green hydrogen as a long-term energy storage medium is being examined; with potential offshore oil drilling platforms too, examining the possibility of blue hydrogen production in sea and piping this to onshore storage bunkers.

For long duration storage, compressed air and hydrogen hydrolysis should be considered. Hydrogen can be used in a fuel cell to generate electricity or be burned to power a turbine. Similarly, compressed air (stored in underground caverns) and liquified air (stored in metal tanks) can be used to spin a turbine[15].

Although hydrogen could be a viable alternative to diesel and jet fuel, it is unclear whether it would be a practical way to store electricity due to the losses of around 70% when creating hydrogen though electrolysis and then using the hydrogen to create electricity. The losses for pumped hydro, liquified air, and compressed air, however, are only around 30%[16].

Therefore, solar PV is a suitable power generation technology for the UK, not just on environmental grounds, as a renewable technology, but on economic grounds, as the lowest cost solution. Despite the additional investment into energy storage required, solar PV is still the most cost-effective solution for power plants commissioning from 2030 onwards.

National Grid UK electricity storage forecasts[17].

What needs to be done to facilitate solar farm access to grid connection, to enable wider distributed energy generation from solar installations?

Having local and smart grids can help solve challenges around connecting to the grid. A much stronger and robust regional energy provision, that has storage capability would certainly contribute to the near-term removal of brownouts in the future. For example, in Guildford, where the University of Surrey is based, there is a barrier to the construction of new factories due to the lack of spare capacity in the electricity grid. A local smart grid would help solve this.

Over production can be used to created hydrogen / stored energy. The University of Surrey has a spin out, Clean H2[18], working on this, and with local partners SSE and Qinetiq we are looking to create a novel green hydrogen platform for substitution of fossil fuels in non-grid connected regions or regions in which there is limited grid capacity at present.

New technology and processes such as these that can generate green hydrogen in a cost-effective way are widely applicable and can be used for both on-shore and off-shore generation to enable energy distribution in an efficient and environmentally friendly manner.

Does Government policy and current planning guidance adequately address the issues raised by proposals to install solar farms on land with high agricultural or ecological value?

Current policy is clear in terms of what constitutes high value agricultural and ecological land. Nevertheless, a more nuanced and flexible approach into determining what types of development would be appropriate is needed.

Advances in solar technology mean that the infrastructure impact of instalments are lessening, and different types of technologies can be deployed in different locations based on their suitability in terms of the local environment and land use.

For instance, solar panels constructed from different materials can allow “filtered light” to pass through to plant life and crops below. If the plants prefer blue-light or red-light, the solar cells can absorb in the green-band or vice-versa. Furthermore, the height at which panels are set can enable different combined land uses that do not damage or negatively impact the ecological or agricultural value of the land.

A case-by-case approach should be adopted that enables landowners and farmers to explore solutions that are appropriate to the local environment.

How sustainable is the supply chain for solar panel manufacture? Do levels of sustainability differ between mature and emergent technologies?

Currently, the manufacture of solar panels requires toxic chemicals like cadmium and lead, but in smaller amounts. Solar panels have the lifespan of 20 to 30 years and during the dismantling of solar power plant, large number of wastes has been disposed. Usually, silicon cells are recyclable, but due to the addition of notorious chemicals, recycling requires considerable amount of energy, and it is expensive too. To reduce the cost of disposal, many manufacturing companies are disposing them in the landfills and transporting the wastes to the developing countries like Africa[19].

Nevertheless, the carbon footprint is much lower than nuclear. Carbon emission from a nuclear reactor is 78 to 178 g-CO2/kWh. Out of this 64 to 100g-CO2/kWh from background grid. In addition to that, all nuclear reactors emit 4.4 g-CO2/kWh from the water vapour they release while solar and wind turbines reduce the heat and vapour by 2.2 g-CO2/kWh results in 6.6 g-CO2/kWh[20].

Scientists are exploring the new innovations to purify silicon for solar cells, and even looking at a new generation of organic solar cells which will revolutionise the costs and payback times of traditional solar cells within the next 3-5 yrs. ‘Organic-inorganic' solar cell technology is a new technology where the efficiency of the solar cells is better than the silicon solar cells, but the material itself were made up of a very small fraction of lead. Therefore, there is an opportunity for further research and innovation in manufacturing solar cell technologies for better waste management.

Solar power generated from solar panels is emission free, but during the manufacturing of solar panels, there are pollutants like sulphur hexafluoride (SF6) associated with it. SF6 is one of the most dangerous greenhouse gas emissions, which has started increasing rapidly into the atmosphere. But renewable technologies like solar, wind, and other technologies, has resulted in lots of connections to the electricity grid and therefore, requirements of electrical switches and circuit breakers have increased.

SF6 produce 23,500 times more global warming compared to CO2[21]. One of the biggest challenges in switching is to replace SF6 gas and to make them eco-friendly. Therefore, some modern switch gear designs have been developed with dual gases such as a SF6 and Fluor ketone mix to make the switching easier. To achieve net zero targets, necessary steps are required to alter our energy infrastructure. Development is needed in switchgear insulating gas technology to overcome the GHG emission, along with the proper protection to circuits.

Does the concentrated global distribution of solar panel supply chains (80% manufacture in China) pose a risk to solar technology expansion in the UK? If so, how could this be mitigated?

There is a synergistic relationship with Chinese solar manufacturers, much akin to the OPEC deals struck early in the oil-petroleum distribution to be made. Most of the main solar companies may have manufacture based in China, but their HQs are overseas, and operate as large corporates without political interferences.

Examining the top ten solar cell manufacture companies in the world, more than half have their sales and operations run from north America, and therefore will pose as much of a threat as semiconductor IC chip shortages for computers, where once more the UK has no indigenous IC chip manufacture capabilities.

It is wrong to consider a global crisis on solar panel supply chains to restrict expansion in the UK, where our usage will amount to a small fraction of the rest of the world current deployment and future usage.

Are there opportunities for solar energy generated abroad (e.g., in the Sahara Desert) to be delivered to the UK via interconnectors?

Some opportunities present via interconnects. With the low cost of solar deployment, governments should consider the use of small inhabitable islands and land crops to be cultivated for solar and wind energy with a PPA managed as an interconnect. A new commodity market could be provided for such use that could be monetised by the city with the current low cost in solar farm installations. Such a move would need to ensure that local populations are well served and benefit from such land uses.

There is a major opportunity to be exploited at present for both solar and wind. LCOE is dominated by the capital cost, efficiency factor over its lifetime and total installed cost. The global averaged LCOE of solar PV has reduced by 91% from 0.378 $/kWh in 2010 to 0.033 $/kWh in 2019. The most recent auction in Portugal recorded about 0.01120 €/kWh and it is 0.012 £/kWh [79]. Average yearly module prices in UK goes down by 50%. When this is now compared to the cost of electricity and gas it is abundantly clear why the business case is present for a new regulatory framework for potentially unused land masses/islands to be used to generate both solar and wind energy for the UK.

Interconnectors are high voltage HVDC cables which connect the electricity system to the neighbouring countries[22]. They are useful for exporting and importing renewable energy between the nearby countries safely and reliably. From 1986, IFA (70km) connects to France, with enough capacity to power 2million homes. From 2011, Britned (260km) connects to Netherlands, with capacity to power 1 million homes. From 2019, Nemolink (140km) connects to Belgium, with capacity to power 1 million homes. From 2020, IFA2 (240km) connects to France, with capacity to power 1 million homes. From 2021, North Sea link (720km) connects to Norway, with capacity to power 1.4 million homes. Now, UK is working on Viking – a new Interconnector of 760Km by 2023, which connects to Denmark, with capacity to power 1.4 million homes[23]. By 2030, 90% of energy imported will be from zero carbon sources[24].

Instead of connecting one by one to the shore, multi-purpose interconnectors connect clusters of windfarms all together and plug it to the energy system of neighbouring countries. In the future, a multi-purpose approach could enable the offshore wind and interconnection to act as a combined asset.

To achieve the net zero target, UK and European countries need to work together as they have similar targets. 75GW of offshore wind energy is required to achieve the target by 2050, which is 10times of energy production today. National Grid UK[25] has revealed discussions involving two European countries about building an energy island in the North Sea. Energy islands will be a great source of energy generation in the future.

December 2022