The Challange with Solar Farms in High Latitudes

An interesting way to look at the impact of latitude and clouds on solar power is to look at how much area would have to be covered to ensure that 90% of the year a solar plant generated the a guaranteed minimum. This affects the cost of the plant and the electricity it generates.

From [1], the map below shows the area required to ensure at least 100MW of daily average power is generated for 90% of the year. This still leaves more than a month where the plant output would be less than 100MW.

For this study, it took 1.4 square km of solar panels to provide a minimum of 100 MW average daily power in southern California and 3.2 square km in Seattle to get the same for 11 months out of the year. This is more than twice the solar panels required for a difference of 1500 km.

This chart highlights the big challenges with using solar in northern Europe and Canada. A mix of solar and wind, which helps smooth out intermittence and reduces storage required is harder to achieve at higher latitudes. It also makes it clear that alternative means of cleanly firming the grid has a high value there. This is one of the reasons that space based solar power (SBSP) is among the energy research priorities in the UK with the Space Energy Initiative and at ESA SOLARIS.

References:
[1] "How Dynamic Cloud Cover affects Solar Power Plant Output", Brady Stoll, 2012, [LINK]