People with rooftop solar systems almost always ask about using batteries to store their energy for nighttime use. Tesla recently announced an off-grid battery storage system, SolarCity announced a home backup power system, and a dozen other companies already have comparable products on the market. These announcements have re-energized (grin) the hype and excitement in this new product category. But are these systems practical and will they save you money?
For the vast majority of homeowners, the answer is “no” to both questions. Only if you have a completely off-grid application — such as a cabin in the woods — can the new generation of lithium ion battery backup systems combined with solar be more practical and cost effective than traditional lead acid batteries. If you are currently on the grid, energy arbitrage makes no sense at all: with current electric rates it is simply not cost effective to generate your own energy with solar during the day and use it at night (or buy cheap electricity at night and sell it back during the day).
In a nutshell, the life cycle cost of the batteries outweigh any potential savings. If you are looking for backup power during a blackout, a generator is still the cheapest way to power your house for a few hours or a few days.
Nevertheless, there is no doubt that batteries will continue to improve, and control electronics will get cheaper and more efficient. Besides the current off-grid and backup power applications of home energy storage, there will come a time in the future when home energy arbitrage (buy low and sell high) and grid support services will make economic sense. If you’re curious about the practicality of home battery storage systems, please Listen Up to this week’s Energy Show on Renewable Energy World.
About The Energy Show
As energy costs consume more and more of our hard-earned dollars, we as consumers really start to pay attention. But we don’t have to resign ourselves to $5/gallon gas prices, $200/month electric bills and $500 heating bills. There are literally hundreds of products, tricks and techniques that we can use to dramatically reduce these costs — very affordably.
The Energy Show on Renewable Energy World is a weekly 20-minute podcast that provides tips and advice to reduce your home and business energy consumption. Every week we’ll cover topics that will help cut your energy bill, explain new products and technologies in plain English, and cut through the hype so that you can make smart and cost-effective energy choices.
About Your Host
Barry Cinnamon is a long-time advocate of renewable energy and is a widely recognized solar power expert. In 2001 he founded Akeena Solar — which grew to become the largest national residential solar installer by the middle of the last decade with over 10,000 rooftop customers coast to coast. He partnered with Westinghouse to create Westinghouse Solar in 2010, and sold the company in 2012.
His pioneering work on reducing costs of rooftop solar power systems include Andalay, the first solar panel with integrated racking, grounding and wiring; the first UL listed AC solar panel; and the first fully “plug and play” AC solar panel. His current efforts are focused on reducing the soft costs for solar power systems, which cause system prices in the U.S. to be double those of Germany.
Although Barry may be known for his outspoken work in the solar industry, he has hands-on experience with a wide range of energy saving technologies. He’s been doing residential energy audits since the punch card days, developed one of the first ground-source heat pumps in the early ‘80s, and always abides by the Laws of Thermodynamics.
Lead image: Green microphone via Shutterstock