Alternatives to Renewables

Some say that renewables cannot expand fast enough to deal with the climate crisis.  That in the end is a matter of political will- technologically, they can be ramped up to meet all our needs, the ramp rate however depends on how much support they are given. If, instead, support is given to other options, then the negative conclusion becomes self fulfilling.

The most obvious alternative is nuclear power. That is not doing well at present most places in the world, with its economics looking very problematic compared to all else, including renewables, but resources do still flow to it. And the nuclear lobby is still very strong, forever churning out promotional material. Even the usually hard-headed Financial Times occasionally succumbs, as with a piece by Jonathan Ford on 17th Nov 2019, in which he said ‘nuclear power remains one of the few technologies the world has for reliably generating zero-carbon electricity’. As was quickly pointed out by academic critics, the evidence base suggests that, taking account the full nuclear fuel cycle (uranium mining, fuel enrichment, construction of power stations and the waste stream), nuclear has CO2 emissions 10-18 times those of renewables. And, in the light of major accidents, incidents, technical failures and outages, it is certainly difficult to see how the world’s ageing nuclear fleet can be described as ‘reliable’. Quite apart from the other issues, like where to put the wastes and how to keep terrorists at bay and also avoid the spread of bomb making capacity. Even its supporters seem to be having doubts at least about some of the proposed ways ahead. 

What about other alternatives? One rather desperate option is geo-engineering, including proposals for reducing the incidence of solar energy, i.e. blocking out sunlight in various ways. That involves mostly unproven and environmentally uncertain technology.  It would surely make more sense to deal with the problem at source and to accelerate the switch to zero emission technologies, using solar energy rather than blocking it, while cutting back on fossil fuel use.

Carbon Capture and Storage (CCS) is another option, enabling us to continue to use fossil fuels for a while, assuming we can find space to store the captured CO2 safely and indefinitely. That looks likely to be expensive and risky- can we really find places to store all our continuing emissions for ever?  A variant of this approach, avoiding the need for storage,  is to convert the the CO2 into a new fuel, possibly using hydrogen produced via electrolysis, powered by renewable electricity. Its sometime called Carbon Capture and Utilisation- CCU. However, it may not be sensible to use green electricity in this way- surely better to use in direct rather than to create a new synfuel, which, when burnt would create more CO2.  

Another CCS-type option, with the same storage space limitations, is the direct air capture and then storage of CO2 - DACCS. That may help to reduce CO2 levels, but energy is needed to run the system. Although using renewable power for that is possible, it may not make much sense. It may be more productive just to use that power direct, so as to reduce the amount of new CO2 being generated from fossil fuelled plants- and vehicles.  That would be even more the case with Direct Air Capture and Utilisation - using the CO2 and yet more renewable power (for the hydrogen) to make new fuels– for burning. 

There are some other negative emission technologies that might be tried, including BECCS- Biomass Energy with Carbon Capture and Storage. To have a significant impact on CO2 levels, that would have to involve huge biomass plantations and huge CO2 stores. We may not have room to do much of this. It might any way be easier to plant more trees and let them store CO2.  We really have to stop deforestation and plant more for a wide range of reasons. Sadly though, even with a massive effort, there won’t be enough space available for trees to deal with all the carbon were already emitted, much less any new CO2 we produce - and trees do eventually die, rot or burn releasing the CO2 again.  That doesn’t mean we should not do what we can this way- it’s a cheap option. Same for soil sequestration- that’s valuable too. However, even on optimistic estimates, carbon capture by whatever means is not enough to deal with the climate crisis, and it certainly should not be seen as an alternative to cutting emissions at source by using renewables instead of fossil fuel.

The same can be achieved by energy saving - it avoids the need to generate CO2. However, it should not be seen as an alternative to renewables, or just an additional option. We need both: however much energy we save we will still need some energy and renewables are, arguably, the best bet for that, while energy saving actually helps renewables - making it easier for them to meet the reduced demand: it’s a good very compatible option.

So based on this quick tour through the alternative options, while renewables and energy saving look good, nuclear looks pretty irrelevant, and most of the carbon capture options have problems and limitations, at best sweeping CO2 under the carpet in the hope that it will stay there, at worst making new synfuels, to add more CO2 back again. Carbon capture also deflect us from the most effective long term approach, reducing emissions at source- based on renewables, along with energy efficiency.

In reality, however, we are faced with all these options fighting for support and resources, in a policy context in which ‘cutting net CO2 levels’ is seen as the key aim, almost regardless of how it is done. That can lead to real problems, as my next two post will describe. Carbon capture and ‘negative emission technologies’ (NETs) are lumped in with renewables as helping to achieve ‘net zero carbon’. Whereas in fact CCS and NETs are basically about letting us continue to burn fossil fuel- for a while. The same can be said about adapting to climate change. Adaptation and emergency measures may be desperately needed to limit impacts, but they will not stop climate change. Indeed, they may worsen it longer term, not least by soaking up resources that could have been spent on renewables and energy saving.

As my next post suggests, it’s a difficult trade off.  Renewables will take time to have an impact on CO2 levels and so there will still be urgent problems to face from climate change impacts. But they will just get worse, if we don’t cut CO2 generation, making adaptive and emergency responses ever more expensive and in the end futile.

There is no question that we are facing problems, global growth in renewable investment has faltered, and emissions continue to rise, at least in some countries, threatening to undermine the Paris climate targets. However, the solution is to redouble (and more) our efforts to expand renewables and energy saving - and cut coal use. There are some hopeful signs- global emission may be stabilising, but there is a lot more to do.  We will have to spend money on emergency measures to deal with climate impacts, but Carbon Capture in most guises is at best a temporary fix and at worst a dangerous, futile, diversion.  Just like nuclear. The renewables are better alternatives.