The solar industry as we once knew it is a thing of the past. We've moved into a new era where the industry is defined not by solar alone, but by the integration of daytime solar power and nighttime battery storage.
My passion for solar dates back 40+ years when, as a mechanical engineering student at MIT, I was part of a research team exploring new active and passive solar technologies. I got hooked on solar and I've never looked back.
What we envisioned in those early days of thermal solar technology has evolved into the rapidly growing photovoltaic industry of today. 40 years ago I never would have believed that rooftop solar is the cheapest energy source for our society. And now, with the development of lithium ion battery technology, integrated solar + storage systems are the best way to keep our 21st century lifestyle cranking when the sun goes down.
There are good reasons why.
To begin with, battery technology has evolved to the point where the economics are compelling. Altruistic aspirations that clean energy will save the world are admirable, but if the economics don't add up, dreams cannot sustain an industry. Batteries have become a practical and cost-effective addition for most solar system installations.
As we transition to an electrified economy, it is apparent that the archaic 19th century electric grid developed by Edison and Westinghouse can't keep up with our requirements. That grid depends on long distance transmission of electricity, which is expensive compared to rooftop solar. Plus, the reliability of the grid has gone down. Outages have become more frequent and unpredictable as extreme weather gets worse and the country's energy infrastructure gets older and more vulnerable. Solar systems can't provide 24/7 power during a blackout. But with battery backup they can.
As the grid's reliability deteriorates, our 21st century lifestyle is jeopardized. Electricity usage is on the rise – even as the grid gets frailer. These days smartphones are our flashlights, electric cars are becoming mainstream, and cost-conscious consumers are flocking to high efficiency heat pumps to keep their homes warm. With a solar system alone, these grid dependent options are rendered virtually useless when the power goes out. To quote the castaways on Gilligan's Island: "no phone, no lights, no motor car, not a single luxury…" Solar itself saves money – but only when the sun is shining. Adding battery storage provides true energy independence.
The benefits of battery systems are instantly apparent to customers. But there are challenges designing systems that meet these customer expectations. As a long-time battery installer, there are three main features that customers want – even when they can't identify these characteristics when they start shopping.
First, customers want an affordable and easy-to-install battery system, in many cases one that can be added to their existing solar system. AC coupled systems – essentially battery backup systems that include a built-in inverter – are the easiest type of systems to install. And easier means more affordable.
Second, once they get into the buying process, customers realize that they want to back up their whole home. For budgetary reasons, adding more batteries and inverters is often not an option. Integrated load shedding and load management technology, coupled with inverters with a high surge capacity, is the most cost-effective way to provide practical whole home backup capabilities.
Third, once customers are ready to buy a system, their contractor must find a code-compliant location for one or more batteries. Sounds easy, but recent building codes are so restrictive that it can be a challenge to find an acceptable location for even one battery – especially for smaller homes. Garages and basements are usually a "no." Outdoors along the side of the house is the best remaining option, but batteries must be 3 feet from most windows, doors and other batteries. Battery system manufacturers who have passed the UL-9540a large-scale fire tests have the most flexibility in siting their home battery systems.
One of the newest systems on the market, the FranklinWH battery, excels in all three of these important customer criteria. First, FranklinWH systems are AC coupled, so they are compatible with the 2+ million rooftop systems already installed in the U.S. Second, the FranklinWH gateway (basically a transfer switch) has integrated load shedding and load management via their app. These features mean that most customers can achieve practical whole home backup without extensive re-wiring. Third, FranklinWH has passed the UL-9540a large-scale fire tests, thereby providing more options to site multiple batteries. The combination of these three criteria adds to the most affordable whole home backup systems on the market – and one that uses the safer LFP battery chemistry.
Transitioning a solar installation business to a battery + solar installation business is challenging. In my opinion there are two key factors for success. First is having experienced residential electricians on staff who are certified battery system installers. Second is selecting the right product. I consider the relatively new FranklinWH battery system to be right up there with industry leaders SolarEdge, Tesla and Enphase when it comes to features, safety and ease of installation.
Barry Cinnamon heads up Cinnamon Energy Systems, a San Jose residential and commercial solar and energy storage contractor. He is also the host of the weekly Energy Show – a regular series of consumer-focused podcasts and videos. His rooftop tinkering led to the development of the first integrated racking systems, Andalay Solar and Spice Solar, as well as the first UL-listed AC solar modules. After 10,000+ installations while at the helm of Akeena and Westinghouse Solar, he's developed a pretty good perspective on the real-world economics of rooftop solar — as well as the best products and services for homeowners, manufacturers and installers.