Floating Offshore Wind Data Mapping Activity ? Question How can floating offshore wind help meet electricity demand when other renewables are not available?
Background We don’t use electricity at the same rate at all times during the day. The amount of electricity that we need all the time is called baseload power. It is the minimum amount of electricity that is needed 24 hours a day, 7 days a week. However, during the day at different times, and depending upon the weather and other factors, the amount of power that we use increases by different amounts. We use more power during the week than on the weekends because it is needed for offices and schools. We use more electricity during the summer than the winter because we need to keep our buildings cool. An increase in demand during specific times of the day or year is called peak demand. This peak demand represents the additional power above baseload power that a power company must be able to produce as needed. When we consider locations for installing equipment to harness renewable energy, we must carefully study the resources available and the energy demands of the region. In this section, we will analyze the wind and solar resources on the west coast of the U.S. and the electricity demands in the adjacent areas.
Electricity Demand On a typical day, the electricity demand starts to go up around 5 a.m. when people begin waking up to get ready for school and work. Demand goes up even more in the afternoon as people start to go home to make dinner and relax for the evening, but businesses remain open. Later in the evening, the demand begins to drop off as people go to bed for the night and businesses shut down. (See Figure 1)
Figure 1: Average hourly electricity load during a typical day by region in different seasons. Data from EIA.
Average Monthly Solar Irradiance in 2019 100
Diurnal Cycles
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Electricity generation from photovoltaics (solar panels) depends on having enough solar irradiation or radiation from the sun. This varies by latitude, season, and cloud cover. The timing of solar irradiation and the timing of electricity demands are key considerations. See Figure 2 for an example of the pattern of solar irradiation experienced in some parts of California.
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A diurnal cycle is any pattern that recurs every 24 hours as a result of one full rotation of the Earth around its own axis. Both solar and wind energy are impacted by diurnal cycles.
Northern CA
Figure 2: Average monthly solar irradiance in northern and southern California in 2019. Data from The National Solar Radiation Database
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Floating Offshore Wind Teacher & Student Guide
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