nuclear-news

Launching the paper, Differences in carbon emissions reduction between countries pursuing renewable electricity versus nuclear power, the SPRU group said that countries with large national nuclear programmes do not tend to show significantly lower carbon emissions. It claims the study shows that nuclear and renewable energy programmes do not tend to co-exist well in low-carbon energy systems because they crowd each other out.

……  the researchers claim that an expanding nuclear programme is no guarantee of reduced carbon emissions – unlike increasing commitment to renewables.

The authors found little support for the suggestion that countries with a large investment in nuclear invested less in renewables. But they said in a challenge to scenarios like that of the IEA, that “strong claims in favour of particular technologies” are “underevidenced”………

The International Energy Agency concluded in a report last year that global nuclear power development is moving too slowly to allow the world to meet its Sustainable Development Scenarios

Over the COVID months, NGESO found that it had a power surplus to manage. It had to artificially increase demand, by paying neighbouring countries to accept power via interconnectors (against market prices). It also used innovative approaches, including inviting users to be paid to increase demand.

Both were necessary, along with paying some renewable sources to switch off and ensuring pumped storage plants were working in “pump” mode, in order to bring demand up to exceed low-carbon supply enough to allow it to call up thermal generation (gas and biomas) to provide stability.

What was nuclear’s role in this period? It too has large rotating machinery and it can provide inertia. But, although the system operator maintains frequency across the entire network, voltage support has to be localised.

What is more, the amount of fast-acting reserves that the system operator is legally required to hold in readiness depends on the size of the largest system in-feed. Sizewell B, at 1200 megawatts (MW) the GB system’s largest infeed, all at one site, was simply too large for the best operation of the system with volumes down by some 20%.

In the end, NGESO negotiated a one off, fixed term contract with EDF to reduce output from Sizewell B by half to 625MW. According to reports, the four-month deal would involve payment from NGESO (and eventually customers) to EDF of between £34m and £46m, depending on market power prices.

That is a significant proportion of the additional balancing costs incurred between March and July 2020, which totalled £718m – 39% higher than NGESO would normally expect costs to be in this period, according to regulator Ofgem.

The arrangement helped give NGESO what it called “footroom” to call on the thermal plant to meet system needs, but it was an inflexible option.

In contrast other measures to provide footroom, inviting small generators to turn down, brought forward over 1 gigawatts (GW) of response across a wide area. Participants could be called upon with just a few hours notice from the system operator.

That result should sound a warning for nuclear operators that argue they are flexible.  The nuclear industry will have to do a lot of convincing if it wants to become the low-carbon companion to renewables.  https://www.nsenergybusiness.com/news/nuclear-renewables-electricity-grids/?fbclid=IwAR1el0Rra5_ir2etNYpo_yz9MAqg2Fm-ekwy4Pjff3ACdiQtflTrN2oysks