Take a minute to look at the diagram above. Note the bidirectional meter in the upper right part of the diagram. If you live in a standard home with an electric bill your electric meter only flows electricity into your home, from the electric company to you.
When you install solar panels the local electric utility switches out your old meter for a bidirectional meter that measures the flow of electricity in and OUT of your home. This is what a bidirectional meter looks like in real life:
At least in Florida there is no cost from the utility to install this meter, the new bidirectional meter replaces your old analog meter.
The old analog electric meter on your home costs the electric company more money because it requires meter readers. The new bidirectional meters allow your electric company to measure your usage remotely without the labor costs of an employee.
Most of the current electric grid is a “dumb grid”, this means that the electric company has no idea how much electricity is needed at any given time in any given area. This is why during the summer months the local utility has to generate more power to keep your air conditioning running.
This increase in power demand (on a 95 degree summer day) is the reason that we have rolling brownouts and blackouts. Recently higher than normal temps in Australia have caused blackouts:
As residential solar becomes more commonplace, the electric company can use the data from bidirectional meters to allocate power in a more efficient way. For instance, a housing development that contains 30 or 40 homes with solar will be able to self-generate enough extra electricity to keep the AC running for other non-solar homes in the same subdivision. This is less strain on the grid during a high demand period.
Residential solar connected to bidirectional meters will make the entire power grid smarter, more efficient, and more reliable. If a car accident or storm takes down local power lines the smart grid should be able to divert rooftop solar power to that area.
Over time more local energy storage will be built into the smart grid, and daytime solar will be stored for auxiliary power at night. One place to store extra energy might even be electric cars, but this won’t happen until battery tech takes another leap forward.
That will be my next blog post!
Ben Alexander
March . 2017