L R AS Published on Saturday 14 April 2018 - n° 229 - Categories:the American PV, RE
Replacing gas-fired power plants with renewable energies?
A Bloomberg NEF (Future of Energy Summit) symposium looked at how renewable energies associated with energy storage compete with gas-fired power plants. Already, the authorities are reducing the deployment of coal, gas or nuclear power plants in the United States and Europe: new constructions are
in negligible numbers. Even gas-fired combined-cycle power plants may no longer be popular because they are slow to build up pressure and are used more for continuous production. For example, the construction of combined-cycle power plants was halved in 2016 and halved again in 2017, according to the findings of gas turbine manufacturer Wärtsilä.
In California, regulators are choosing renewable energy with storage rather than gas-fired power plants. Similarly in the state of Michigan. In Minnesota, by law, new gas-fired power stations must be proven to be competitive with solar plus storage.
California has also reduced the amount of natural gas it consumes as an electricity generator since 2014. This was made possible in 2017 by the mild climate and the production of hydroelectricity.
Of course, renewable energy prices have fallen, but this is not the only argument in favour of this technology: while single-cycle gas-fired power plants can quickly increase and decrease their output as needed, battery storage comes into play even more quickly. This is a major argument because the intermittency of RE requires a very flexible response.
The debate remains open on the exact role that RE plus storage can play. Storage will disrupt the transmission and distribution of energy.
In California, in the last month alone, due to distributed generation and efficiency, there have been 20 cancellations and 23 revisions of transmission projects. This has saved $2.6 billion. The non-replacement of gas-fired power plants and unnecessary transmission infrastructure increases the threat of RE: less generation capacity and fewer transmission lines will reduce the profitability of power producers and distribution owners.
RE, even though cheaper than conventional energy, will not eliminate conventional energy. Studies have shown that it would be expensive to integrate 80% wind or solar power even with the widespread use of batteries. Therefore, greater flexibility in energy demand should be considered. The problem remains in the Nordic countries of transferring the energy harvested between seasons. Flexible energy production (hydroelectricity or gas) will be needed. Lithium batteries will not be able to ensure this transfer.
The very sharp rise in the price of lithium and cobalt included in batteries is already creating disruptions, even though we are far from reaching a renewable energy rate of 80%. According to the author, there is no short-term shortage of lithium-ion. On the other hand, for cobalt, of which 64% of world production comes from the Democratic Republic of Congo, the prognosis is more reserved. On this subject, analysts at the Massachusetts Institute of Technology (MIT) predict that there will be no real supply constraints in the medium term, but that there may be occasional supply shortages, making it necessary to open more mines to meet the growing demand for batteries for electric vehicles.
PV Magazine of 12 April
