California Governor Jerry Brown recently signed into law a sweeping and admittedly ambitious bill that requires the state to produce half of its electricity from renewable sources by 2030 while also doubling its energy efficiency.
While the law did not specify exactly how the state will accomplish this, industry experts say utility-scale solar is likely to comprise a large part of its new energy strategy. While solar is becoming more advanced with each passing month there are still baked-in assumptions that issues with where to place such facilities and how to transmit the produced power can be solved. The bill also seems to require innovations in energy storage.
“Looking at present trends, we'll see a lot more solar photovoltaics at utility-scale size,” said Ethan Elkind, the University of California's associate director of climate change. “Barring other policy developments and technology changes that will be the main contributor.”
While the bill is clearly ambitious the state's solar revolution is already well underway. California produced over 44,000 gigawatt hours of renewable electricity in 2014, which accounted for about 20 percent of its total usage. This was produced by a mix of methods such as geothermal, biomass, hydro under 30 megawatts, wind and solar.
By 2020 over 33 percent of its power will come from renewables.
California's 2030 goal would be unviable for a good many other states, but California is unique. The “cost for developing solar in California is now comparable to the cost for developing natural gas fired plants,” says Josh Hohn, the founder of APA’s energy initiative.
Instead of construction costs the main issue will be how that energy is stored and enabling utilities to seamlessly switch from storing to delivering electricity.
Batteries are set to play a big role but it will also take so-called 'demand-response' strategies. Solar energy is usually produced in the middle of the day, a time when power consumption is fairly low.
An example of such strategies is PG&E's push to create abundant solar-powered electric vehicle charging stations.
This would remove surplus solar energy during the daytime, while at the same time reducing evening electricity demand. PG&E, in addition to having a more balanced supply-demand equation, would see increased revenues from each addition vehicle using its stations.
The idea isn't just a concept. The utility already presented a proposal to build over 25,000 charging stations at a cost of $654 million but the California Public Utilities Commission vetoed the plan. Instead it approved a smaller-scale project for 2,510 stations.
California, despite not approving PG&E's mega-project, is intensely interested in pushing electric vehicles. Transportation is the number one source of greenhouse gas emissions, accounting for 38 percent of total emissions produced by the state.
Another option to help balance supply and demand for solar power is the idea of using old electric vehicle batteries to store the surplus power produced during the day. Nissan and General Motors have already announced plans to repurpose batteries from trade-in Leaf and Volt vehicles.
Elkind say that repurposing old vehicle batteries “is very promising... [and] will be a critical piece to balancing renewables."
Electric vehicle maker Tesla motors clearly understands this. Its already launched a range of batteries for both home and industry and looks set to produce even more. Its 'gigafactory', currently under construction in Nevada, won't just produce batteries for its electric cars. One of the primary goals is to produce cheap battery storage systems - just the kind that will be needed for California to hit its 2030 target.