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Business View Magazine
energy calculations to its solar partner, Solar City, who
designs the home’s rooftop solar photovoltaic array.
“Our solar partner does the engineering based on the
geo-locale of the home – they know exactly how much
sunshine they get in that location, based on histori-
cal data – and then they size the system to produce
as much energy as their calculations indicate. Now,
here’s the caveat for that scenario: this is all based
on the guidelines on how the home is to be used. So,
if you leave your sliding doors open on a hot summer
day for ten hours, you will have energy costs – there’s
no question about it. However, if you use the home like
it normally would be used, you will still get an electric
bill, but it will just say ‘zero’ on it. Now, the other caveat
of the net-zero energy concept is that in the summer
months, you might have a twenty-dollar bill, but in the
winter months, you will have a twenty-dollar credit. So,
in the course of a year, you have a net-zero cost home.
That’s how that works.” A third caveat is that in places
where the electricity is created by solar energy but the
water is heated by gas, the homes cannot be called
net-zero energy homes, but rather net-zero electric
homes.
The twenty-dollar credit to which Salmi alludes is based
on the concept of “net-metering.” With net-metering,
when a home’s solar system is making more electricity
than is being consumed, such as on a long, sunny day,
all of those excess electrons flow back into the power
grid and the home’s electric meter goes backwards.
Florida, like almost every other state in the country,
has enacted net metering statutes that allow consum-
ers to sell homemade electricity back to their power
companies.
In order to have an efficient zero-energy home, how-
ever, the solar system has to be aligned with other en-
ergy-saving components. “The elements that we put
in our homes include, of course, the solar, but we also
have home automation as a standard element in every
