Becoming Your Own Power Company
NEW YORK ( MainStreet) These are interesting times in the power industry.
Solar technology is proven. Customers have signed up in droves, anxious to not only capture their own power but to sell what remains back to the utility companies.
Utilities, meanwhile, have become wary. Some are dramatically lowering what they pay for "net metering" power, even though those supplies peak along with air-conditioning demand. Others are imposing new charges on solar panel owners, claiming they are "freeloading" on wires other customers must pay for.
For consumers, the ultimate solution here is to unplug from the grid entirely. That means adding storage to a system, or some power source that will turn on when the solar power goes away.
Can it be done?
One way to do it is to store excess power through an inverter and battery, converting it to AC power when needed. Outback Power of Arlington, Wash. offers a full line of inverters under the Radian name, which a solar installer may add to your order.
Solar cells create Direct Current (DC), and many older panels include micro-inverters that turn this into Alternating Current (AC) for use in your home or for sale to the power company. Batteries store power as DC, too, so if you add your own battery to an existing solar system you're going back-and-forth a lot.
There is some loss in the process. If you have ever checked the box on the power line between your laptop and the wall, you may have found it warm. That box is an inverter, and that heat is power lost in conversion between the wall's AC power and your computer's DC.
Commercial installers will size an inverter-battery to a panel system's power output, and add a Load Center to handle movements of power in the background. The parts for such a system may cost $3,000 to $5,000, and for an office complex, apartment complex, warehouse or large store they make a lot of sense.
The aim is to "zero out the grid," storing power locally when it's abundant, delivering it for use when it's needed, and handling the power spikes and surges that utility customers just suffer through .
In residential markets, however, utilities are trying to freeze-out even battery storage. SolarCity (SCTY) recently paused its effort to sell battery back-up on its systems, citing an 8-10 week back-up on applications.
But this is merely a market pause. A recent Goldman Sachs report on Tesla Motors (TSLA) said the company's plans to deliver batteries at $125/KwH will let residences power themselves with solar for no more than it costs to buy electricity from a utility, within a few years .
The Tesla batteries will face a number of competitors, some offering different storage technologies, assuring a competitive market, according to SmartGridNews.