Right now in America, there are about 2 million homes with solar panels. Considering there are about 90 million single-family homes, that doesn't seem like much. But consider this: we are now on track to add a million new solar power systems each year. It took a while to get here, but solar power is increasingly becoming a popular choice to power the Home of the Future.
The number of solar-powered homes "is going to get better pretty fast," says Justin Baca, vice president of markets and research for the Solar Energy Industries Association. Panels are getting cheaper, growth is happening at double-digit rates every year, and some key politicians are getting excited: California recently passed a requirement that new homes include solar panels.
"We are personally looking forward to a day when solar power is as ubiquitous as AC."
Of course, not all states are as weather-lucky as California, but several solar companies say they are beginning to expand beyond Golden State and Florida. Anne Hoskins, policy director for Sunrun, the nation's largest residential solar installation company, says the company is growing in states like Wisconsin and Illinois. David Bywater, CEO of Vivint Solar, says his company has many solar power customers in New England. Baca points out that Maryland and the Carolinas are starting to have more solar panels, and New Hampshire and Vermont have quite a bit when the size of the states is taken into account.
Most houses with solar panels are still connected to the traditional electrical grid. Cloudy days (and eclipses) will occur, and that's when it will be helpful to stay connected. Normally, when the system produces more energy than necessary, they export to the grid. And when they produce less, they take from the network. Costs are based on consumption, says Baca. You're not supposed to export much more than you consume, so systems tend to be designed to be a little smaller than what is needed for 100 percent. (Usually they will target 80 to 90 percent solar power.)
But that doesn't mean that being 100% off the grid isn't possible, Bywater says. Energy storage is key when it comes to renewable energy at any scale; you want to have a security. There are a few different ways to store energy, but the one that's most useful at home is to use a lithium-ion battery, similar to the one in your phone, but much, much larger. These can be connected to the solar panel system and store energy during sunny days. Then they go into operation when the clouds appear.
Although solar energy is cheaper and increasingly popular, the industry faces some obstacles. Permits and inspection regimes are fragmented, explains Baca. Different jurisdictions and local governments have different versions of the building code, and they all interpret them differently. "That creates a very fragmented and inconsistent process that makes companies have to worry about installing solar energy," he says. For example, they could sell to a homeowner who is excited about panels. But the permitting process takes three months, and then the customer gets frustrated and cancels. So while the California legislation was a win for the solar industry, it could be the outlier. Politics remains a bottleneck.
If solar power becomes ubiquitous, we are likely to see it integrated with smart home energy management systems, Bywater predicts. These will regulate the home battery by using different sensors and solar panels. "The real trick is for the system to know how to make someone feel comfortable and how to be aggressive in conserving energy," he says. Know the optimal home temperature and how to change it based on utility rates and time of day to save money.
Ultimately, says Baca, "we are personally looking forward to a day when solar power is as ubiquitous as alternating current." Very few places had air conditioners when the technology first became available, and now it is rare to find a builder who will create a new home without it. "People think something is missing when it's not there," he says. "I think that's where we're going with solar power, and I hope we see it sooner rather than later."
By Angela Chen
Original article (in English)