Battery Systems

Maximize your solar system, and shield yourself against power failure.

Backup Batteries

Back-up power is for everyone, though the investment is more attractive if you own your home. Peak-shaving and load-shifting systems are good for people who have their own account with the Utility company. 

Battery systems are either AC-coupled or DC-coupled. If you have solar, either option will work for you. If you don’t have solar, then an AC-coupled system is the best solution. Either type can provide back-up power, peak-shaving, and load-shifting. The latter two can be provided with a simpler system.

Photo of a battery backup system attached to an external home wall, next to a large jade plant.

A Deeper Dive

A battery system is a stored source of power. This can be useful in a variety of ways.

  1. Back-up power in case of Utility outage - this is what most people think of right off the bat.

  2. Peak-shaving - this reduces your electrical usage from the Utility grid at a given point in time. This is of most benefit to customers who are on a commercial rate plan where they are charged based on their highest electrical demand in the past 365 days.

  3. Load-Shifting - this is of most benefit to customers on a Time-of-Use rate plan (TOU).  Mostly commercial properties, and residential solar customers. The battery is used during peak pricing periods (typically from ~4pm-9pm) so that the customer is NOT using the expensive Utility power, but instead, power that was stored (or generated) during a lower pricing period (typically ~8am-4pm).

Any of these systems can have a generator input, so that you can recharge your batteries from a propane, gasoline, or diesel generator. Soon, there will also be options for connecting your EV. We anticipate this will be commonplace in the next 2-5 years. The nitty gritty of battery backup:

Peak-shaving/Load-shifting only system components:

  1. Main service panel

  2. Inverter (battery or hybrid battery/solar)

  3. Battery

The inverter has sensors that measure the load on the main service panel (MSP). For peak-shaving, the inverter is set to use battery power when the load (or demand) on the MSP is at a certain level. For load-shifting, the inverter is set to use battery power based on the time of day, so it measures the load on the panel and supplies enough power from the battery to offset that load

Backup system components - AC-coupled:

  1. Main service panel

  2. Critical loads panel (backup panel)

  3. Battery inverter

  4. Battery

  5. Generator (optional)

Important loads are moved to the “critical loads panel” and are fed directly from the battery inverter. When the Utility Grid is active, the inverter uses this power to supply the loads on the panel; when the Utility Grid is down the inverter will pull power from the battery to supply the loads. When the battery is depleted, the critical loads will no longer be able to run, unless charged by another power source (solar, grid or generator).

Backup system components - DC-coupled:

  1. Main service panel

  2. Automatic Transfer Switch

  3. Critical loads panel

  4. Hybrid solar/battery inverter

  5. Solar panels

  6. Battery

  7. Generator (optional)

Like an AC-coupled system, important loads are moved to the “critical loads panel”, but are now fed directly from the hybrid solar/battery inverter; when the Utility grid is active, the inverter uses this power to supply the loads on the panel; when the Utility grid is down the inverter will pull power from the battery to supply the loads. The crucial difference here is that if the grid is down for a day or more, the system can recharge the battery and supply the critical loads with solar energy. 

 

What do you need to have to get one? 

Power, or a need for it, somewhere. These systems have been installed in RVs, boats, and remote facilities for decades.

For home or business, you’ll need approval from the city or county, and the Utility company.  We are very familiar with the approval process, and we can handle everything once we know exactly what you are looking for.

What to expect?

The first step is to have a conversation about what you’re looking for. The design process will take about 1-2 weeks, and permitting can take 1-6 weeks. Actual construction scales with the project, but a minimum of 1 week for basic projects.

How to get started:

Fill out this form and we will contact you to start a conversation. A few pictures go a long way towards shaping the discussion.