Behind the Meter: Optimizing today’s solar systems.
The vast majority of PV solar systems today are grid tied. This means that there are no batteries and any excess power that the building doesn’t use travels out to the power lines and on to the next property. This is an efficient way to share power back and forth with the power company, as well as eliminate the need for batteries to store excess power.
Until recently this “net metering” arrangement meant that the power company received power during the day and gave it back to the customer at night – an equal give and take. The property made the power and gave it to the power company to sell to the next customer then would receive the power back when the sun went down.
For many power companies, net metering arrangements have changed. Now, in many cases, the power company receives the power and then gives a set amount of money to the home producer. This amount is often quite a bit lower than the retail cost of the power and makes the payoff for a PV system quite a bit longer. And, as these rates are revised periodically, there is no way to know what payments will look like in the future.
So, as we analyze the payoff for a modern on-grid system we have to look further into a number of factors that can help in understanding the pay back.
This post focuses on the amount of behind the meter power that will be produced.
Behind the Meter power is the power that is consumed by the building that never hits the grid. For instance, if the base load (amount of consistent power the home uses) is 1KWh then when the sun is shining at least 1KWh will stay “behind the meter” and the power company will never see it. If we shift loads while the sun is shining from loads we would normally use when the sun isn’t, we increase the amount of behind the meter power.
Water heating, laundry, dishwashing and electrical heating are all things that, if able to be shifted to sunlight hours, keeps more of the power behind the meter.
Behind the meter power is the most efficient use of solar energy. The sun hits the array, comes directly into the house and is used instantly. There is no power line loss and no distance traveled. This is identical to the original net metering before the net metering rules changed.
So as you consider solar, work with PAREI to help you discover the potential for behind the meter power. If optimized, the payoff time for your solar system could be greatly reduced.
