Nuclear Production of Hydrogen, Fourth Information Exchange ...

NUCLEAR HYDROGEN USING HIGH TEMPERATURE ELECTROLYSIS AND LIGHT WATER REACTORS FOR PEAK ELECTRICITY PRODUCTION
The power demand of electrolysers and power outputs of oxy-hydrogen turbines can be changed
very rapidly compared to traditional peak-electricity production technologies. Consequently, these
systems can be used for power regulation to produce higher quality electricity (constant voltage and
frequency). This is a very high value utility service.
Reserve power (spinning reserve)
Reserve power fills the need to provide generating capacity in the event that an electrical generator
goes off-line for unexpected reasons. This is presently done by putting online additional power plants
that run at partial load with the capability to produce more power if another unit goes off-line. This
process represents expensive backup power. When electrolysers are operating, they can provide the
spinning reserve because they can be quickly turned off. Oxy-hydrogen turbines can provide spinning
reserve by operating at low power levels, with the capability to rapidly go to full power. For this
application, high power output must be provided for periods of time – from tens of minutes to a few
hours – the time required to start up another power generation system.
Load shifting and load levelling
The demand for electricity varies by the time of day, the week and the season. The cost and price of
electricity are high at times of peak power demand and low at times of low power demand. The high
cost of peak power reflects the fact that the facilities needed to produce much of this power are
operated for only a few hundred or a thousand hours per year. This is shown in Table 2, which lists
the marginal prices of electricity in 2004 for nine US electric grids (FERC, 2004).
Table 2: Electricity prices for 2004 versus the number of hours for different electrical grids
$ per
ISO New
Arizona Florida
Com.
Seattle
Southern
AEP LADWP
MW(e)-h
England
PS P&L
Edison
PJM
95 – 181 4 2 20 25 – 30 175
Total
hours
8 784 8 784 8 784 8 784 8 784 8 784 8 784 8 784 8 784
The table shows the number of hours per year that electricity could be bought or sold for a
particular price range [indicated in dollars per megawatt (electrical)-hour]. The prices of electricity for
a few hours per year can be much higher. For example, the Texas grid (ERCOT) has had spot market
prices as high as $1 500 MW(e)-h.
162 NUCLEAR PRODUCTION OF HYDROGEN – © OECD/NEA 2010