Tim Faulkner: Solar-energy batteries and big storm outages

Many trick-or-treaters ventured through southern New England neighborhoods afflicted by the latest widescale power outages, caused by the big storm of Oct. 29-30. Some houses were lit by generators, others arbitrarily spared from the blackout. To grown-ups at least, the Halloween displays were far less scary than the darkened homes with spoiling food and a lack of heat.

After a string of blackouts in recent years, it’s hard to blame homeowners for wanting backup power such as portable generators. The noisy, gas engines are more common since storms such as Sandy and Nemo have hit the region during the past five years. Some homeowners have even installed large, permanent standby units fueled by a direct hookup to a natural-gas line.

Property owners have reason to look for backup energy. Extended power outages are more common, in part because of higher winds and more powerful storms fueled by climate change.

Generator choices and prices vary widely. Portables start at $150. Quieter, cleaner and more powerful models can be as much as $5,000 or more. Permanent, standby units are priced upwards of $4,000 to as much as $25,000.

Adding backup battery storage to a solar array costs about $12,000, or about $8,400 after a federal tax credit.  That’s on top of the price of panels and equipment, which typically cost between $12,000 and $25,000 for the average home. Current rebates and incentives cut the expense by about 40 percent.

While the price may be high for the solar + storage, consumers are looking.

“There is huge interest for energy storage. We get calls all the time,” said Doug Sabetti, owner of Newport Solar, based in North Kingstown, R.I.

The first thing that residential customers want to know is whether they can go off the grid. Sabetti explained that cutting ties with the power grid is complicated and expensive. Several renewable incentives require a grid connection. So far, Sabetti has installed one solar + battery unit, but as incentives improve and hardware cost drop, the option of solar backup with grid connection will become more common.

Nationally, Tesla launched the solar + storage movement with the release of its Powerwall lithium battery storage pack in 2015. Sales have been slow and Tesla has shifted its focus to commercial customers, who use batteries to lower energy costs during peak demand. Tesla still offers solar + storage to residential customers through its SolarCity subsidiary. Other national installers such as Sunrun are expanding into the residential market using the Tesla Powerwall.

These systems are grid-connected, allowing for financial discounts and other benefits. In principal, the systems sell excess power back to the grid. And, of course, when the power goes out, the lights and refrigerator stay on.

However, not all states are prepared for permitting new solar + storage systems. Massachusetts and Rhode Island support the model and regulators are clarifying the rules.

One problem: solar regulations don’t state whether battery storage can be coupled with net metering, the process of taking and sending electricity to the grid at the regular retail price for power. Utilities such as National Grid don’t want customers charging their batteries off the grid when prices are low and selling the electricity back to the grid when prices are higher.

In September, the Massachusetts Department of Public Utilities issued a temporary ruling allowing net metering solar + storage systems while it further investigates the implications of those systems.

Sunrun and Tesla have a petition before the Rhode Island Public Utilities Commission (PUC) that limits the size of eligible solar + storage systems to 25 kilowatts or smaller and batteries can only be charged by the sun and not from the power grid. The docket is supported by the Office of Energy Resources and the Northeast Clean Energy Council. National Grid generally favors the concept but wants the rules clarified. The PUC may rule on the petition at its Nov. 27 meeting.

Another approach to ensuring that the power stays on is to create municipally owned electric utilities. The U.S. Energy Information Administration reports that public utilities have fewer power outages. National Grid, a for-profit company, was criticized for its response to the recent lengthy power outages in the region.

Rhode Island state Rep. Aaron Regunberg (D.-Providence) plans to introduce legislation when the General Assembly convenes in January that would allow more public, nonprofit utilities to operate in the state. Currently, the Pascoag Utility District is the only municipal electric utility in Rhode Island. Massachusetts has 41 municipally owned electric utilities. None have been created since the 1920s, and bills allowing new ones to form have stalled for years in the Legislature.

Proponents of public utilities say they invest in community projects, including renewable energy.

Tim Faulkner reports and writes for ecoRI News.