We looked at examples of solar arrays and were told about how they could be used in commerce. They can be inequitable, because the feed-in tariff for a £15k panel is equivalent to £1,000 a year, so it is a better investment than a savings account. It benefits the rich, contributing to the wealth gap, because only they can afford the initial capital investment.
There is also a grid variability issue for private solar arrays. On the plus side, however, the oldest solar panel at CAT was inspected after fifteen years and it was still almost fully as efficient as at installation. Furthermore, a solar panel on a house can pay for itself in 2-3 years, although a wind turbine would be a better investment due to the payback time being only six months.
One of the most interesting methods of micro-generation we saw was a micro-hydro turbine. The turbines available in the home usually generate between 0.8 and 4 Kw, although they have gone out of fashion somewhat. Perhaps they are less viable than might be assumed after seeing the turbine at CAT; they have a reservoir 30m above the actual site, something that is obviously not available to most.
The latter part of our visit was spent in the WISE Centre (Welsh Institute for Sustainable Education), a building constructed with earth bricks, made from compressed earth with high thermal mass and low embodied energy. They absorb energy in hot weather and release it in cold weather. They are also rendered with lime, and not fired to as high a temperature as plaster, saving energy in the construction process. On the roof were solar thermal evacuation tubes to provide hot water to the building; they provide more efficient water heating and are even efficient in winter due to the insulated pipes. This superb lecture venue hosted the three presentations mentioned below.
The Offshore Valuation
The Offshore Valuation, a report chaired and coordinated by the Public Interest Research Centre with the aid of the Scottish government, DECC and the Crown Estate among others, shows the massive potential for UK to export renewable energy at scale. Estimates for the UK's offshore renewable energy resource included technologies including fixed and floating wind turbines, tidal and wave generation.
Floating wind is a new technology and there is currently a demonstration unit off the coast of Norway, pioneered by Norwegian oil firm, 'Statoil'. The 'floating' offshore wind resource was found to be much larger than the fixed offshore wind resource because it can penetrate areas much further out to sea. Of the total practical resource of 2100TWh/year, floating wind accounted for 1533TWh/year. The UK could then become a net energy producer, exporting to Europe. Statoil's pioneering design for floating wind turbines have 85m of the turbine underwater, attached to the sea floor with chains.
The report found overall that the total practical offshore resource is 6 times larger than the UK's current energy consumption, even if only 14% of the total sea area were used. This could replace 1 Billion barrels of oil and directly create 145,000 new jobs, without even including the supply chain.
The report recommended that any new offshore wind sites should be made 'super-grid' compliant, so they can eventually be integrated into a Europe-wide electricity network. It also recommends Britain to take a leadership role in the 'super-grid' discussions in Europe and evaluate new financial structures to fund the necessary infrastructure.
One key challenge with be in financing the turbines, since it is a new technology considered risky by investors. Unlocking this finance looks to be down to the UK's new Green Investment Bank, which will help prove the viability of investment. Once installed the wind turbines can pay for themselves in a few years and earn an income for the UK by exporting energy.
This report makes the DECC Energy Pathway Calculator appear extremely conservative in its estimates. DECC's 'level 4', radical scenario, only includes up to 120GW of installed offshore wind capacity, whereas this study found that 400GW of offshore capacity was feasible. The study to determine the 'practical resource' also included more than 50 factors including avoiding flight paths and areas that are important for wildlife and conservation, so that the impact on wildlife would be minimal.
Zero Carbon Britain 2030
Zero Carbon Britain 2030 goes far beyond the UK's target of cutting carbon emissions by 80% by 2050 and aims to make Great Britain a carbon-neutral nation by 2030. It describes itself as a 'fully integrated solution to climate change', drawing together experts from the Centre for Alternative Technology, the Open University and individuals such as Nobel Peace Prize winner, Sir John Houghton to create a detailed framework to radically reduced greenhouse gas emissions in the UK. The five sections of the report - Context, 'PowerDown', 'PowerUp', 'LandUse' and Framework - detail 56% cuts in energy demand, generation of 55% of energy from offshore wind, 75% reduction in the amount of meat and dairy consumed, 10% of carbon emissions sequestered using 'biochar', reforestry and soil storage and no use of new nuclear or coal plants - even those with 'carbon capture and storage'.
This highly ambitious report is the first to deal with climate change as a whole, rather than individual elements of it - such as the Offshore Valuation. This removes some specificity but makes it a valuable tool to show that climate change is a solvable problem, and well within humanity's resources to do so. It provides a framework which governments can - if not follow precisely - use to build a model of how emissions will be reduced overall. It has some flaws - a few panel members were concerned at its heavy reliance on carbon sequestration - but it still provides a hugely valuable resource. Go to zerocarbonbritain.com to view more detailed information on the report.
How does this affect our report and DECC?
The final presentation we received looked to make links between and compare the DECC 2050 Pathways work, the Offshore Valuation and the Zero Carbon Britain 2030 report. This presentation was given by Martin Kemp, who works at CAT, and was the lead author of the zero carbon Britain report.
The first question raised was ambition. Do we want to design 2050 visions that just scrape the 80% target, or do we want to be a bit more aspirational and use CAT's findings to suggest a zero or a close to zero pathway?
CAT will also be submitting a response to DECC about the 2050 Pathways calculator – flagging up where there is more than 10% discrepancy between their scenario and the top level on the calculator. The largest variance between DECC’s figures and CAT’s are for:
- Offshore wind – DECC’s “maxed out” scenario 4 – which implies that further technological innovation would be required -is only around half that denoted as “practical” within the offshore study.
- Aviation and international shipping - within with Zero Carbon Britain scenraio there is a 2/3rd reduction in air travel – but on the DECC model there is no demand side option and the supply side option is extremely unambitious.
- Geo sequestration – CAT took the best literature on sequestration and then subjected these figures to discounting.
- Tom Williams, Scouts; Helena Wright, Young Friends of the Earth; Tom Youngman, Green Flag School; Eleanor Carter, BTCV.