Self-Consumption PV Systems: Page 8 of 10

What is your perspective on grid defection?
Do you think this form of self-consumption will gain traction in certain markets?

It will gain traction if the PV financials are favorable to owners and if utilities continue to create an environment that promotes it. Overall, grid defection and load defection is not the direction we should be going in to increase our use of renewable energy; but if utility resistance to distributed PV continues, it will become a more viable option. I anticipate requirements where residential customers either cannot disconnect from the grid, as exist in Florida, or have to pay exit fees that make leaving the grid a costly decision. Exit fees are already common for commercial customers.

Marvin Hamon, PE, Hamon Engineering

Grid defection is an emotional response rooted in frustration with utility policy. Producing all your own power 24 hours a day, 365 days a year is a big job and isn’t easily compatible with the typical modern lifestyle. Hawaii is probably the easiest place in the US to do so, but even Hawaii has clouds. Do we really want backup generators running all over the islands when a storm rolls through? The Rocky Mountain Institute differentiates between grid defection (cutting the cord) and load defection (reducing the reliance on the grid). Most folks will want to build out their solar-plus-storage system yet remain connected to the grid, as long as the utilities wise up and don’t institute punitive shortsighted rate structures that drive distributed solar off the grid.

Wes Kennedy, Fronius USA

We hear from a lot of people who don’t like their utilities and want to take their 4,000-square-foot home with dual air conditioning units off grid. These homes can consume 100 kWh per day. In this scenario, the answer is not to couple solar with massive storage or to add a large dirty gas generator. The best solution is typically to stay grid tied and to add solar and storage for self-consumption and critical emergency power.

Neil Maguire, JuiceBox

It’s a hell of a lot of hype and spin at present. In the near term at least (6–36 months), formerly grid-tied, battery-based off-grid systems will be very few and far between, at least in my market in Hawaii. 

Marco Mangelsdorf, ProVision Solar

Today, off grid is only a small part of the US PV market. It is still more cost-effective for homeowners to stay connected to the grid and to use the PV and grid resources interchangeably. With combined PV and storage, homeowners can increase their level of energy independence, in many cases producing and storing all the energy they need. However, to be fully disconnected from the grid does incur added costs and lifestyle changes.

Peter Mathews, SolarEdge

This seems to be a universal fear of most utility companies. They are suffering from allowing various companies to get between them and their customers with PPA contracts. Now they are overreacting to the prospect of PV plus storage, which could enable their customers to disconnect and become their own utility companies. Unless utilities dramatically increase their general service charges, it would be foolish to isolate your property from the option of maintaining access to convenient utility power via an infrastructure that is already in place. I prefer to think of the utility service as a cheap backup generator when there isn’t enough PV generation or when there is a problem with your distributed generation system.

I do think this form of self-generation will become popular in markets with extremely high utility-tariff rates. We are already seeing demand grow in many island markets, including Hawaii. In some markets, the local governments are incentivizing relatively small, isolated village power systems rather than funding expensive transmission projects to serve remote villages. Some village power projects have successfully integrated PV, wind, batteries and backup generators. These applications are becoming more commonplace, given the reduction in PV and battery prices, combined with the increase of utility power prices.

Kent Sheldon, Greensmith Energy Management Systems

Article Discussion

Related Articles