Solar + storage

What does storage have to do with solar?

Battery banks like these can provide emergency power during grid outages and reduce peak demand charges for businesses.

Solar + storage is an ideal combination. Most rooftop solar systems are grid-tied which means that when the power goes down your solar system automatically shuts off. Solar with batteries can allow a building to stay on line and serve its power needs when the power goes out. Solar charges the storage and keeps it ready for action when the grid is operating.

If the grid goes down, stored energy takes over to meet power demands. This applies to homes and businesses, as well as vital service providers in the community such as hospitals, shelters, and community centers. Together, they can keep critical electrical services running for individuals and communities in the event of an emergency.

Storage is likely to become a key component of an improved electric grid where the production, management, and consumption of energy is managed by users across the grid. Solar + storage is closely tied with efforts for grid reform.

Solar + battery storage uses

Solar systems with battery backup can provide individuals and communities with much needed resiliency in the face of natural disasters. These systems can protect vulnerable communities from the disaster’s most immediate and devastating effects by providing power when the electric grid goes down. Over an extended period, solar-powered systems replenish batteries, even if roads are cut off, or access to fuel for traditional home generators is unavailable or hard to get.

Solar + storage can provide homeowners with high-quality backup or “premium power” in the event of a utility outage. This comes at a cost. Adding battery storage to a solar array can increase costs so much that the savings seen on utility bills are negligible. Homeowners in areas with poor power reliability may still choose to invest in storage to keep critical loads, such as refrigerators, working when utility power goes out. In other areas where utility tariffs boost the price of electricity higher outside of solar’s normal hours of production, storage can significantly improve solar’s economics by storing the array’s energy and shifting the use of that energy in the home to later or earlier in the day to avoid using the more expensive non-solar energy.

Solar + storage can make financial sense for institutions. This is especially true for commercial entities facing high demand charges in their regular electric bill. Storage combined with specialized energy software can reduce an institution’s demand for utility power at key times, reducing all of their energy costs. Despite this, interest on the private sector side for solar storage remains low due to a lack of knowledge about storage, the complexity of such projects, and a lack of incentive for businesses to invest in resiliency in any form. On the public side, municipalities can encourage solar + storage as part of their resiliency goal. However, solar + storage is not frequently included in the local resiliency planning.

Creating value and resiliency for communities

This diagram shows how battery storage can enable you to use the electricity generated by solar any time of day.

Storage technology is changing fast. It offers not only resiliency benefits but financial ones as well. Organizations and businesses can use solar + storage to reduce their costs and protect citizens from natural disasters.

The main barrier to growing solar + storage isn’t due to technical limitations or a lack of public support; it’s cost. While new storage technologies are being rapidly developed and the cost of both small and large-scale systems is dropping, energy storage still only makes sense in certain markets.

While costs are major obstacles, energy storage policies and regulations can contribute significantly to widespread deployment and economic feasibility. Solar + storage assets tend to be deployed in locations where local regulations enable energy storage to make sense – either where additional incentives for stored energy are offered or other traditional generators are too costly.

It is becoming increasingly feasible to add back-up storage solutions to our most important institutions, including hospitals, fire departments, police stations, and shelters that provide critical emergency services. Cities like San Francisco are already incorporating solar + storage into emergency response plans to improve resilience. New York is promoting micro-grids that often feature solar + storage as central components in their resiliency planning.

Watch our recorded webinar on storage

Download the slides

Solar + storage resources

Our work

  • We’ve put together a comprehensive guide for homeowners who are interested in battery storage. Click here to download it.
  • We’ve conducted an in-depth analysis of the current “state of the art” of solar + storage. We wanted to determine whether solar + storage is a viable way to protect vulnerable communities from the impacts of climate change. The research used the Hampton Roads, Virginia region as a test case. We modeled the financial feasibility of these projects and identified ways to scale up their deployment. Download the full report on solar + storage for resiliency.
  • Our Maryland Storage Co-op Pilot is our first co-op to be focused on adding battery storage to existing solar systems. The co-op is currently in process, with co-op participants receiving their first storage installations in the summer of 2018.

Learn more about solar + storage in your state

  • D.C.


  • Florida


  • Maryland


  • Virginia


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