Our Thoughts on Battery Backup

Many people, both existing and prospective customers, have reached out to Same Sun and asked us to install battery backup storage for their solar arrays. While the technology is exciting; everyone wants their solar array to provide power in the dark or during a power outage, we do not recommend this course of action.

Here are a few of the reasons:

  • We Do Not Think the Expense is Justifiable.  Unlike solar, there will never be a return on investment for battery backup. To do it right and have sustained power during an extended winter outage the cost is $25,000 – $35,000.
  • It is Not Environmentally Friendly.  Unlike batteries that power your vehicle thus replacing gas and oil the precious commodities such as graphite, lithium, nickel, manganese, and cobalt will only be used on rare occasions for convenience. Additionally, moving power back and forth from solar or the grid to the battery backup creates a loss of kWhs.
  • It is Not Reliable.  We have installed several battery backup systems, including right here in our own office to test the technology.  In our experience, we have been called upon to service 60 – 70% of these projects. We do not believe this is viable.
  • It May Not be Safe. We have concerns that our state is relying on individual manufacturers’ safety codes. Vermont does not inspect the installs.
  • Battery Lease Programs Disqualify You for Maximizing Savings.  If you are a GMP customer that is leasing your battery or part of their program that uses the battery to mitigate peak demand, you are not allowed to switch to Rate 11, which is the most advantageous billing rate for a solar customer.  See our previously published blog post about Rate 11 here. Also, GMP will be accessing your battery at peak demand times, possibly having it low or drained when you need the power due to an outage.
  • Today’s Batteries May Soon be Obsolete. Soon, there will be a bidirectional charger for all vehicles that will allow you to use your Electric Vehicle as battery backup for your home. The resources used to make car batteries are justifiable because driving an EV directly reduces oil and gasoline production, and lowers emissions.

While we wish that there was an inexpensive environmentally friendly and reliable battery back-up storage – this is not our experience.  If you have frequent power outages or this is a concern for you, we recommend that you have your essential loads placed into a subpanel and then get a conventional generator sized proportionately.

Please Contact Us with any questions.