We all have stories about losing power in our home for several hours—or days—and many people suspect that power interruptions are becoming more frequent. They may be right; unfortunately, the utility data are so sketchy that nobody can say for certain. But declining investment in maintenance on the part of utilities, plus the increased frequency of extreme weather caused by climate change, are almost certain to keep the blackouts coming.
One response is to buy a home generator. That’s understandable, and it’s justified for homes with critical needs. After Hurricane Sandy, generator sales are booming. But on-site generators are expensive, dangerous, and dirty. They are also unreliable, which consumers discover only when they actually need one. That’s the supply-side solution; but it’s also worth considering how greater energy efficiency might play a role in dealing with the problem of blackouts.
Insulating a home beyond code makes it more blackout survivable. Power outages have an unfortunate habit of happening when it’s hot, cold, or unpleasant outside; indeed, extreme weather is often the cause of the outage. So a reasonable precaution is to enable the home to maintain habitable conditions for as long as possible without heating or cooling. That is best accomplished with more insulation and tighter construction. Installing windows that ensure natural ventilation (without compromising the home’s security) also makes the home more livable during both extreme and normal conditions. Building codes typically require insulation levels suitable for average weather, not for the exceptional cold snap or heat storm. Also, building codes assume that the heating and cooling systems are functioning. That’s not the case when the power is out.
Modest thermal upgrades may be all that is needed to carry a home through a second night without power (and avoid spending a night in a motel or shelter). These upgrades may also prevent the pipes from freezing for a few critical hours. A superefficient refrigerator will prevent food from spoiling for a few more hours, too. Unlike generators, these measures provide benefits all the time, not just during emergencies.
Maintaining operation of sump pumps is key to preventing irreversible damage in low-lying homes during a wet power outage. Many people buy generators first and foremost to power their sump pumps. An especially efficient sump pump makes sense, because it can run longer off a battery, perhaps avoiding the need for a generator altogether. Adding a DC power option—and linking that to a PV unit—would make a home even more self-reliant.
It’s also essential to maintain emergency lighting and communications during a power outage. Rapid progress in LED lighting technologies now allows a superefficient primary lighting system to also function as a backup, possibly with an alternative DC supply. Communications are more challenging. During Hurricane Sandy, subscribers to Verizon’s FiOS network found that their Internet and telephone systems quickly died because the backup batteries failed before the promised eight hours. Network equipment could be designed to switch into more energy-saving modes (mostly by operating at lower rates of data transfer) during blackouts to extend battery life. These modes could also save energy during normal conditions.