Is solar cheaper than nuclear?

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Chris Goodall has a provocative new piece arguing that solar is now cheaper than nuclear power in the UK.

A quote:

At 2013 prices, solar PV in mid-latitude countries is now cheaper than new nuclear. Put in the UK context, the proposed EdF power station at Hinkley is now more expensive per unit of electricity generated than solar farms in the south of England.  The implications of this need a great deal more consideration than they are getting.

By itself, the cost crossover  doesn’t mean that countries shouldn’t invest in nuclear power. Nuclear delivers electricity reliably throughout the year. This baseload power is more valuable than PV’s high levels of output at midday in summer when demand levels are low in most of Europe.

The final sentence here makes it clear that Goodall’s headline “Solar is now cheaper than nuclear. Even in the UK.” is somewhat misleading. If one thing costs slightly less than the other thing, but is less valuable how can you say it is cheaper. This is rather like saying an iPad is cheaper than a MacBook Pro. It doesn’t really tell you a great deal. If someone wants to do some actual work, then they may find the iPad’s lower price is not so enticing. This is even more pronounced with solar power, which reliably delivers zero electricity when the UK’s electricity demand is at its highest, around six pm in Winter. This is a problem too many ignore.

Another analogy. Consider someone who regularly commutes between London and Edinburgh, and normally takes the East Coast train. If he books his ticket a month in advance he can get it for £39.50, which is about 8p per kilometre. Now, imagine someone came along and said they could offer this man a ticket that won’t get him all the way there, it may go to York, it may go to Peterborough, but it works out “cheaper” at 7p per kilometre. You can be sure that he will immediately look at how much it would cost to finish his journey. Things appear rather similar for claims that solar is cheaper.

We also have to consider that we can build as much solar power as we like in the UK and still be able to yank it out and have a functioning electricity grid. Solar power is completely unable to displace conventional power plants, we need the juice most precisely when there is no solar. If we had some storage in place you could displace a little, but not much (note that last year Germany solar power in December was 10% of what it was in May.) So, for large scale solar you need to ask how much it will cost to build the gas plants to run when there’s no solar, and to keep them running. Another bad omen from Germany: last year it got a bit under 5% of its electricity from solar, yet got over 50% one afternoon. A simple projection from this is that going above 10% overall will see days when total solar output exceeds electricity demand. This will force one of two things to happen: the excess electricity is stored (expensive) or simply curtailed (again, expensive). Either way it is clear that getting much above 10% solar will require a significant reduction in solar power’s capacity factor or the need to store a significant amount of it.

Unless these realities are factored into cost estimates I’ll remain skeptical of any claim that solar power is cheaper than nuclear or any other technique for generating electricity.


4 thoughts on “Is solar cheaper than nuclear?

    joffan7 said:
    May 16, 2013 at 8:02 pm

    Presumably “Germany solar power in December was 10% of what it was in December” -> “German solar power in December was 10% of what it was in June”


    Samuel said:
    May 16, 2013 at 8:38 pm

    Chris looks also quite optimistic regarding the capital cost and do not take in account the completely artificial prices of solar panels due to the Chinese dumping. The EU proposed anti-dumping taxe is of 47% !!!


    leepforward said:
    May 16, 2013 at 8:39 pm

    This is a very interesting post, thanks.

    I recently asked someone heavily involved in the solar sector what the total cost, including installation and FIT subsidies (at current levels) would be to install an average 4kw solar system on all of the roughly 30 million homes in the UK.

    His estimate was:

    FIT = £14,919,672,000/year
    Install cost = £225,000,000,000

    So, over 25 years of subsidy and working life of the panels, I get that to a staggering £597 billion or £23,919,672,000/year.

    These panels would generate 96.63 tWh/year, so roughly 30% of UK annual consumption 325.8 tWh/year.

    But as you rightly say, only during the day and not when we need it most.

    And it’s also based on current demand…if we’re serious about decarbonising energy, then the 83% of homes heated with gas now will have to convert to all electric space heating – which would push up electricity demand even further, thus rendering solar’s contribution even less significant.

    Is this a reason not to make solar part of the overall energy mix? No, probably not. But what it shows is that solar alone is never going to be the answer.


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