Cloudy Climates Can’t Stop Clear Savings
Electric cooperatives seeking to maneuver into or maintain a position as an energy authority to their members will invariably receive questions and concerns from members interested in potential solar installations, be they cooperative-initiated, large-scale projects, or home- or business-level arrays. Often, such queries will pertain to the target location’s climate, and if a certain amount of cloud cover might adversely affect such an endeavor.
If you were asked to name countries with climates best suited to solar energy production, England and Germany likely would not top the list. Germany gets about as much sun as Alaska (which isn’t all that much), and England is famous for clouds, fogs, mists, drizzles, and damp. Yet these two countries top the charts among the top ten nations by total solar power capacity. There are several reasons solar has gained so much ground in cloudy and sunny places alike, and co-ops are in a great position to show their members why.
Photovoltaic (PV) cells will convert any kind of sunlight—direct, diffuse, and reflected—into energy. While it’s true that PV cells have the highest output with direct sunlight, that doesn’t mean they simply stop providing value when the clouds come rolling through. Even at a fraction of peak production, a solar installation is still adding value to an energy portfolio. Most importantly of all, we should keep in mind that clouds come and go while an installation’s value builds year after year. Neither the peaks nor the valleys are representative of the average added value.
In nearly all technology, heated circuits operate far less efficiently than cooled circuits, and the same applies to PV cells. While a solar array in a hot, arid location may receive more direct sunlight, an array in a more temperate location—even with higher average cloud cover—might outperform the arid installation simply because what sunlight it gets is converted more efficiently. On top of that, an occasional rain effectively washes solar panels and helps prevent soiling which would otherwise drastically impact production. In fact, in arid zones there are entire micro-industries devoted to simply cleaning solar panels because of the lack of rain. It should be noted that more than rain alone is necessary for complete panel maintenance, but rain is still a positive factor to consider.
Batteries, Batteries, Batteries
The leaps and bounds made in energy storage technologies are changing nearly every aspect of the energy industry. There has been a significant reduction in cost of large scale lithium batteries that will soon make PV + storage financially viable. In some markets, it is already viable at current market rates. A good energy storage solution will not only help round out the disparities between high production times and high demand, but helps to smooth uneven collection during cloudy periods. They can even be set up for remote deployment so the batteries and solar array will operate in parallel during peak demand periods.
There are a large number of considerations and dynamics involved in power supplies and demands, but it will pay to keep in mind that a temperate, cloudy climate does not equate to a climate poorly suited to solar, and in fact offers several advantages. For a broader review on solar issues, see our list of solar considerations for co-ops.