National Grid has just published its 2015 Future Energy Scenarios report, which gives four different NatGrid visions of what the UK energy mix might look like in 2035/36. The scenarios are documented in a long report which is heavy on projections and assumptions and light on engineering – in fact I think it would be true to say that there isn’t any. The level of detail (which goes down to “number of appliances by type”, “take-up of cavity wall insulation” and “shorter distance EV charging profile”) also defies analysis in any reasonable time frame. So here I document the results of a quick-and-dirty review conducted by subjecting Gone Green – the most aggressive of NatGrid’s scenarios – to the “February 2013 treatment”. Does NatGrid’s February 2015/36 generation mix fill February 2035/36 electricity demand if weather conditions in that month are the same as they were in February 2013? As might be expected it doesn’t:
Figure 1: National Grid “Gone Green” scenario for February 2035/36, generation deficits factored from February 2013 hourly National Grid data.
A very brief account of how I came up with this result. Figure 70 of the NatGrid spreadsheet shows NatGrid’s 2035/36 Gone Green generation mix, which according to NatGrid cuts CO2 emissions by 87% relative to 2013/2014 levels. (It is not, however, a high-renewables-penetration scenario. Renewables in fact make up only 50% of total generation.) I factored Gridwatch February 2013 generation and demand to match this generation mix. The Table below gives specifics:
Note: I prorated French solar generation for the month to match NatGrid’s 1.3TWh of projected solar generation in February 2035/36. Gridwatch supplies no solar generation data for the UK.
After applying these factors NatGrid’s generation by source for February 2035/36 looks like this:
Figure 2: National Grid “Gone Green” scenario for February 2035/36, generation by source factored from February 2013 hourly National Grid data.
Comparing February 2035/36 total generation from all sources with February 2035/36 demand gives this:
Figure 3: National Grid “Gone Green” scenario for February 2035/36, total generation versus demand factored from February 2013 hourly National Grid data.
And subtracting demand from total generation gives these power surpluses and deficits (the deficits are shown in more detail in Figure 1). They are caused dominantly by the large fluctuations in wind generation. (I’ve made no attempt to estimate how much storage would be needed to balance them out, but once more it would be up in the TWh range):
Figure 4: National Grid “Gone Green” scenario for February 2035/36, generation surpluses and deficits factored from February 2013 hourly National Grid data.
So we can add the NatGrid Gone Green scenario to the DECC and Centre for Alternative Technology scenarios which as discussed in recent posts also won’t work.
NatGrid also has three other scenarios; Low Carbon Life, Slow Progression and No Progression. Would they fill 2035/36 demand? Rather than repeat the Gone Green exercise I short-circuited the process by taking the generation mix graphics in the NatGrid report and replotting them in modified form (Figure 5). I whited-out wind and solar, the two non-dispatchable generation sources, imports, which probably won’t be available when needed in 2035/36, and CCS, which at the present rate of progress may never be commercialized. This leaves only generation from dispatchable sources, which are the only ones that can be relied on to fill demand:
Figure 5: National Grid’s four future energy scenarios with non-dispatchable and other speculative generation sources whited out.
Low Carbon Life and Slow Progression meet emissions targets but have substantially the same generation mixes as Gone Green, indicating that they too will almost certainly not meet demand. No Progression (top right) has a higher proportion of dispatchable generation and therefore a better chance of working, but it’s essentially a business-as-usual scenario that doesn’t meet emissions targets.
The question now has to be asked; why can’t anyone come up with a scenario for a low-carbon, low-emission, renewable energy future that works? Because there isn’t one. At this time we simply don’t have the ability to replace conventional dispatchable generation with large amounts of non-dispatchable renewable generation and still deliver power when needed, which is what the published scenarios attempt to do. The best the UK can hope to do at this point is develop a plan that works and which gets it at least some way down the road towards a green energy future. What might such a plan look like? I’m working on one.