Back in 2015, California opened a 550 MegaWatt solar farm near Joshua Tree National Park. It was the world’s largest. It spans 3,800 acres and generates enough power for 160,000 homes.
Could California get most of its electricity from solar power and other renewables?
First let’s look at the state’s current electricity sources. It gets 10% from solar and another 19% from other renewable sources. That’s a great start and now we need to keep going!
California used about 292,000 GWh of electricity in 2017 from all sources. See Table below from California Energy Commission (CEC).
Ref Cal Energy Commission: http://www.energy.ca.gov/almanac/electricity_data/total_system_power.html
Could Renewable Energy Sources produce most of California’s Electric Power?
Lets look at the numbers. Electricity from non-renewables like coal, gas and nuclear account for 47% of the energy produced. We used 292,039 million kWh of electricity in 2017 so 47% is about 137,000 million kWh.
That would require about 94,000 Megawatt of solar installations. And they would cover about 650,000 acres which is 102 square miles. Assume a total of 5 times that amount, to allow for access and service areas around the solar arrays, transmission lines and include large battery storage sites, that would total 513 square miles.
The state of California’s official land area is 164,000 square miles. So the solar energy systems would cover about 0.3% of the land area, which is tiny. California contains lots of mountain regions, rivers and other unsuitable regions, but 513 square miles of solar array zones spread through the state at suitable locations would use a very small amount of the total land area!
Solar Panels needed for Yearly Production
In California a standard 0.27kW solar panel, at full capacity equivalent of 4.5 hrs per day, produces 0.27×4.5×365= 443 kWh a year.
This would require about 137,000 million/443 = 309 million solar panels.
For California to become an all renewable solar energy State, large solar panel arrays scattered through California in suitable places would require 513 square miles of area, which is about 0.3% of the state’s land surface.
The solar arrays could be installed in the many desert and uninhabitable regions located within a suitable distance to a town or city and to existing transmission lines. Also on the roofs of homes and businesses.
The state would become independent of outside power agencies and be self-sufficient for electricity production to meet all commercial and residential needs.
And its carbon footprint would drop steeply! But that’s another story.