There has never been any shortage of critical commentary on renewables. Indeed, as they succeed and expand more it seems to increase! Australia’s Salt Bush Club is a reliable source of invective in this area. In a recent post it summarised its environmental case against renewables as follows: ‘Green Energy isn’t green. It has a huge cost in rare metals; it creates toxic waste problems; solar panels create solar deserts; turbines chop birds and steal wind and rain from inland areas; and now they want to steal fresh water and energy to export low-energy explosive hydrogen.’
Some of this is old stuff- which is being addressed. That may often only require relatively simple modifications. For example, wind turbine impacts on birds are relatively rare if the wind farms are properly sited, but collision risks can evidently be reduced even more (by 72%) if one blade is painted black. The scale of water use from hydrogen production is a newer issue. Salt Bush say ‘Electrolysis consumes nine tonnes of water …to make one tonne of hydrogen’. That’s true- but does it matter? The Global Warming Policy Foundation has looked critically at the hydrogen option. It notes that the UK Climate Change Committee has projected that the UK might produce 270 TWh of hydrogen by 2050. The GWPF says that would require between 67 billion and 140 billion litres of water per year, 1-2% of current water use in the UK. Not a lot, although not trivial if water gets scarcer in summer as climate change impacts. Though that’s also true of nuclear plant- they need a lot of cooling water.
The Salt Bush Club’s point on materials is more substantial- and has been widely discussed. ‘Clean energy technologies generally require more minerals than fossil fuel-based counterparts. An electric car uses five times as much minerals as a conventional car and an onshore wind plant requires eight times as much minerals as a gas-fired plant of the same capacity’. So says the International Energy Energy in a new report on materials constraints.
While copper, zinc and silicon are the materials most heavily used, there are reasonable, though not large, reserves. Some of the other materials are used in smaller quantities, but the resource is more limited, for example for some rare earth elements, like neodymium, used to make powerful magnets for wind turbines and electric vehicles. Extracting some of these materials, can have major local ecological and biodiversity impacts. And close to two-thirds of the global supply of rare earth elements is in China, which dominates the supply chain.
However, there may be substitutes and opportunities for recycling, and also other sources, which may expand as the market grows. Sea bed mineral extraction is one option - although there are obvious eco-limits. So, there could be significant issues. The World Bank has predicted a 500% rise in the production of minerals like graphite, lithium and cobalt by 2050 to feed the energy transition. Demand on this scale could be hard to meet and that could slow some longer term developments – e.g. of EVs, if Lithium Ion batteries continue to dominate.
The IEA says urgent attention needs to be given to materials issues, and clearly it would help to have new more efficient extraction, processing and utilization technology for key materials, as well as looking to alternatives to using the scarce materials. ‘Many of the techniques for creating sustainable minerals supply still need to be invented,” Bénédicte Cenki-Tok, an associate professor at Montpellier University, wrote in The Conversation. “We must invest in geosciences, create new tools for exploration, extraction, beneficiation and recovery; treat the leftover material from mining as a resource instead of waste; develop urban mining and find substitutes and effective recycling procedures.’
That is already happening with the materials used to make wind turbines. Some now have wooden towers (with, its hoped, 25% less CO2 in production) and recyclable blade materials are being tested, in a move way from fiberglass and carbon composites with textiles being a lighter and more sustainable option. Avoiding or recycling toxic materials is an obvious requirement for PV solar. Some of the more advanced PV cells make use of toxic materials like Gallium Arsenide, but there are now non toxic cells being developed and more attention is also being played to end of life cell management.
More attention is also being played to the impacts of solar arrays on local ecosystems, and although there can be wildlife issues in some desert contexts, this can be avoided and given proper attention to siting, the impacts in most other locations seem to be positive, with PV arrays providing a haven for wildlife and wildflowers. Sites can also be managed to allow for continued farming activity. Indeed sheep grazing can actually aid solar farm operation.
Potential environmental problems can be found with every energy supply technology, new and old. That certainly is the case for fossil and nuclear energy. Hydro and biomass, the ‘old’ renewables, do still have eco-question marks and carbon management issues, but, in the case of most new renewables, given proper attention to siting, the problems seem to be surmountable.
Looking beyond supply technology, the Salt Bush Club also mentioned ‘explosive hydrogen’. Well hydrogen isn’t the answer to all our problems, and it does need energy to make, but it can be produced using green power, so its climate impact can be very low, and it can have multiple roles to play, not least in helping balance variable renewables- and, its getting cheaper! Like most things green. Try harder Salt Bush!
There are of course many other sources of critical comment on renewables and green energy policy, some of them a bit more cogent. And some critics try to run renewables up against nuclear power – even though that is now very much a minority source, supplying only 10% of global power, as against over 26% from renewables, which seem set to expand very rapidly to 50% and beyond. Despite its safety and security risks, nuclear nevertheless still has its advocates, since fission does not generate CO2 directly, but producing the fuel for it does, and, unlike renewables, it’s cost continue to rise. Overall, it does not look like much of solution to climate change, whereas renewables do.
Indeed a new study has shown that, in 123 countries around the world, the uptake of nuclear power over the past 25 years has no significant association with lower emissions, whilst uptake of renewables shows a strong association. It was found that the uptake of nuclear and the uptake of renewables tend to vary negatively with each other, suggesting a strong ‘crowding out’ effect and a possible undermining of climate aims. As one of the reports authors, Prof. Ben Sovacool from SPRU, said ‘Countries planning large-scale investments in new nuclear power are risking suppression of greater climate benefits from alternative renewable energy investments.’
No one is suggesting that there will not be local environmental issues to deal with. We have to take any environmental impact issues seriously. However, far from being a major environmental problem, as Salt Bush and others have claimed, renewables arguably offer good new positive environmental and climate solutions – and are a better bet than nuclear.
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