Backup power options when the lights go off
by Katherine Loving, Contributing Columnist
Power outages can be more than a minor nuisance. Extreme weather can knock out the electric grid for days to weeks at a time. Even for shorter outage durations, the loss of power affects electricity-dependent medical equipment or home-based businesses.
Many users are considering off-grid solutions during prolonged outages. Gas-powered generators are a traditional choice for residential power generation, but new battery storage systems, when coupled with solar panels, can also be a solution. There are pros and cons for each type of backup power system, so consumers should consider their power needs and budget.
First, size your home energy needs to evaluate whether you should power the whole house or just a few critical appliances. Tally the reported energy use of each appliance that needs to remain operational to get a rough estimate of minimal energy needs.
Gas-powered generators have the lowest upfront costs. These can be portable, permanent or standby systems. Portable generators typically cost between $400 and $1,500 and use roughly 20 gallons of gasoline per day. Gas-powered generators are noisy and have the least output, making them more suited to occasional, brief outages.
Portable generators can be manually connected to a circuit panel, but an electrician must install a manual transfer switch to protect appliances and utility crews from a power surge once electricity is restored. If not connected to a circuit breaker, appliances can be plugged directly into the generator but require a long, heavy-duty extension cord for safe operation.
Portable generators also must be operated in well-ventilated areas and shielded from wet weather. The U.S. Consumer Product Safety Commission estimates 80 deaths per year from carbon monoxide exposure are due to improperly operated portable generators.
Permanent, or standby, generators typically cost $2,000 to $5,000 and can have installation costs that run as much as $10,000. These are connected directly to a residence and can be turned on automatically in the event of a power outage. Permanent generators can run on natural gas or propane for extended periods. Standby generators are suitable for frequent outages or occasional but sustained outages.
Overall expenses for a solar and battery storage combination are much higher than a generator. The National Renewable Energy Lab estimates the average U.S. cost for installation to be around $1,200 to $1,500 per kilowatt of system capacity. This estimate includes the cost of the battery, installation, permitting and inspection costs. Adding a battery storage system to an existing solar installation is significantly more expensive and may require an inverter change.
Compared with generators, this option is quieter and does not create local emissions like carbon monoxide. The upside of a solar and battery storage system is the ability to offset the higher initial investment costs through year-round energy savings.
However, a battery storage system can only provide 10 to 15 hours of continuous power. In weather situations that limit solar power generation, this is not a solution.
Though costly, backup systems can bring great peace of mind when the power goes out. If you have questions, contact your local electric cooperative.
Grid-Tied Solar with Battery Storage System
• Quiet operation
• Seamless transition from grid to battery
• Clean, emissions-free energy
• Minimal maintenance
• Excess power can be sometimes
resold back to utility
• High upfront cost
• Requires sunlight to operate or charge
• Requires multiple batteries to power the house
Backup and Standby Generators
• Lower upfront costs
• Higher capacity/longer run times
• No refueling (if connected to propane or natural gas)
• Requires routine maintenance
• Requires propane, natural gas or diesel
Katherine Loving writes on consumer and cooperative affairs for the National Rural Electric Cooperative Association.