Example of output from wind turbine: Vestas wind turbine V164, 8 MW, reaches its maximum 8 MW output at 13 m/s wind speed, but at 6 m/s, the output will be approximately 1.1 MW, and below 4 m/s it will not be operating.
In an energy system that relies on wind energy, at low wind speeds electricity must be produced from dispatchable sources, and the fuel may be green gas. In the Danish energy system, the gas grid is planned to be 100% renewable from 2030 due to the increasing production of biogas and the political decision that individual gas boilers should be converted to DH or individual heat pumps. With the very high capacities of wind power planned for 2030, it is expected that there will be many hours of excess production of renewable electricity. The electricity will be used to produce hydrogen (and from hydrogen green fuels for other sectors) and green gas which will be added to the gas network and blended with fossil gas. The longer-term planning is the day-to-day planning of the balance in the power system, which, among others, considers expected production from intermittent renewable sources, required supplementing production from dispatchable sources (such as CHP plants), or operation of units that can down-regulate the power system.
speeds for the wind turbines to operate at full load. Therefore, it will be necessary to operate dispatchable plants. At other times, at high wind speeds, the consumption of electricity may be limited, and it is necessary to curtail the electricity. In this situation, the DH systems with thermal storage supplied from electric boilers can utilize the otherwise curtailed energy for the benefit of the power system and, of course, for the DH consumers. At a high share of RE in the grid, there will be excess production of electricity, and the power prices will be zero or even negative. Excess electricity must be either curtailed or utilized. Curtailing RE will have socio-economic costs, and the additional costs are paid by the consumers. The prices in the power systems are settled every hour, and by planning the production one day ahead, it is possible to plan the production on the power plants with the lowest costs for the power system. Electric boilers or other flexible consumers are often necessary to avoid curtailing RE production.
Made with FlippingBook - Online magazine maker