Ask Bob — January 2022

Bob Pierce headshotBob Pierce answers questions about energy efficiency, consumer products, and cooperative governance. He is Clearwater Power’s Chief Operating Officer and welcomes your questions on our Ask Bob page.

Q: Is there a way I can use my generator during an outage without buying an expensive transfer switch?

A: Yes! There are two ways to safely utilize a generator during an outage. The main thing is to prevent your generator’s output from back-feeding onto the power line. This is dangerous because if the 120-volt or 240- volt output from your generator flows onto the power line, it will go through the transformer backwards, stepping the voltage up to 7,200 or 14,400 volts. If a lineman is working on the line when this happens, it could cause a fatal accident.

If you want to hardwire your generator into your home wiring, then you will need to hire an electrician to wire in a transfer switch that switches your source power from the utility grid to generator power. This will prevent back-feed. However, there is another, less expensive option that is still safe, albeit less convenient. If you use properly sized extension cords to plug appliances directly into your generator, then you don’t need a transfer switch or an electrician. You are simply keeping your generator’s output completely separate from your home’s wiring and therefore from the power grid.

Make sure your generator is outside while it is running, where it has plenty of ventilation and the carbon monoxide from the exhaust gases cannot enter the home. Then just make sure you don’t overload the extension cords.