Monday, August 1, 2011

Energy after nuclear

With public opposition leading the way, nuclear power is on the defensive nearly everywhere around the world, even in France, where a poll in June showed three quarters of the French people interviewed wanted to withdraw from nuclear, against 22% who back an expansion programme. Globally opposition is running at around 62%, with massive majorities in Italy, Germany and Mexico being against - 94% in Italy’s recent referendum .

Local agitation and grass roots reactions, following Fukushima, has forced governments and parties to rethink- famously in Germany, Switzerland and Italy. Japan has now said it wants to exit from reliance on nuclear, in favour of renewables. And so also now, perhaps, may France, with presidential elections due in May and a policy review of options for future energy mix underway. Energy Minister Eric Besson said ‘We will study all possible scenarios. It will be done with total objectivity, in full transparency, without avoiding any scenario (...) including the scenarios of a nuclear exit.’ One scenario would be a total exit from nuclear by 2050, or even 2040. Reuters noted that shares in EDF, which runs 58 nuclear reactors in France, ‘fell nearly 1% after news that France would examine a full exit from nuclear’.

While the centre-right UMP party mostly supports the extension of nuclear, the opposition Socialist Party has called for a moratorium on new reactors and pledged a national debate on energy transition if elected in 2012. That leaves the UK as one of the few remaining safe havens for nuclear in the western EU, with strong support from the government and only around 52% of the pubic opposing new nuclear. We need to try harder.

Given that France gets 74% of its electricity from nuclear, the French example should help (if they can consider a phase out, anyone one can- the UK only gets 18% and falling), even if cynics may feel that the new French energy review will end up ‘proving’ that France needs nuclear, much as some fear that the German phase out will falter, since not enough investment in renewables will occur, so that nuclear will be ‘needed’ again.

In case a French phase out sound hopeless, do remember that the 74% figure is just the electricity generated at the plants. Some of this is used by the plants themselves and for new fuel fabrication and spent fuel reprocessing (maybe 10%), and some is exported. And then a lot is lost in transmission and distribution (maybe another 10%) on the way to users. Also remember that its only electricity, and that’s typically only about a third of total energy use (even in France which uses a lot for heating). Nuclear generated 410 TWh/y at plants in 2008, with 60 TWh/y being exported, while total primary energy uses was 1,860 TWh/y in 2007. So nuclear met just 22% of France's recent energy demand (if non exported), or 19% with current export arrangements. For comparison, renewables were supplying 12.9 % of primary energy in 2010: IMG/pdf/Rep-env-eng.pdf

So, if nuclear went, it would not be such a huge loss as may first be thought, and given that most of the plants were built around the same time, in the 1970 and early 80,’s , there will be a need for some sort of replacement of them all soon. Now is a good time to take a new path.

That certainly is what Germany is trying to do. It is phasing out all its nuclear plants by 2022. Cynics say that will mean it will use more coal. But actually it is still planning to meet its carbon targets, and expects to do that by a combination of much expanded renewables (35% by 2020 and then in stages up to 80% by 2050), energy efficiency savings, and a switch to natural gas as an interim option. However it can cut emission from some residual coal and gas burning via Carbon Capture and Storage. That will be useful since, for some while, there will be a need for some fossil-fuel backup for the variable renewables, even though the fossil backup plants will only have to run at full power occasionally- and can gradually convert to using biomass.

Of course there are limits to how much biomass and biogas they can get, so they will also need other approaches to balancing variable renewables. There are plenty- most obviously pumped hydro storage (they are building more). And also supergrid links across the EU and beyond, exporting excess wind and solar power and importing green energy from those that have excess, when wind/solar is low in Germany. Geothermal is also being pushed ahead.

In addition, there is also another newer idea- generating ‘green gas’ via electrolysis, using electricity from renewables when there is excess- and then storing it for use when there is lull in renewables. That produces hydrogen, which can then be converted into methane gas – using some CO2. Gas is easy and cheap to store and transmit to where it is needed for heat and power generation, and can also be used in vehicles. Biomass could be used as a carbon feed stock: in effect you would be upgrading it by adding hydrogen. And then, if you also have CCS, and assuming the biogas is produced from renewed biomass, the overall process is net carbon negative. The same would be true if you used CO2 from the air as feed stock, but ‘air capture’ of CO2 is currently very expensive.

Green gas sounds a wonderful idea, providing a truly carbon- free, and indeed potentially carbon negative, back up to intermittent wind power and variable solar power . But won’t all these energy conversions be very inefficient? Well it’s not too bad, since you can use some of the waste heat, though there are still some losses. See the paper from the Fraunhofer institute/ Kassel University at But you do get a flexible storage system. Just what you need if you are going for a massive expansion of renewables. And it’s a way to get valuable green gas without using so much biomass - and land. More at

Some clever green chemistry to see off nukes!

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