Wild Rice Electric Off-Peak Heating: How It Works With Your Furnace or Heat Pump

If you live in Mahnomen County, there's a good chance you're a member of Wild Rice Electric Cooperative, headquartered right in Mahnomen, and a good chance you've heard neighbors talk about off-peak heat. It's one of the most useful ways to lower heating costs around here, but it only works well when your heating equipment is set up for it. Here's a plain-language explanation from the HVAC side.

Note: rates and program rules change. The details below reflect the co-op's published program at the time of writing. Always confirm current rates and requirements directly with Wild Rice Electric before making equipment decisions.

How off-peak heating works

The idea is simple. The co-op buys and delivers power more cheaply when demand is low. During peak periods, usually on the coldest days when everyone's heat is running, it pays more. So Wild Rice Electric offers members a much lower rate on electric heat, in exchange for the right to switch that heat off during peak demand.

Under the program, your electric heating load is put on a separate meter and a receiver that lets the co-op control it. When a control period starts, your electric heat shuts off and a backup heating system carries the house until the control period ends. According to the co-op's published program, the electric heat can be controlled for up to eight hours in any one day, off-peak kilowatt-hours are billed at a reduced rate (listed at 6.76 cents per kWh at the time of writing), and members must maintain a 30-day supply of backup fuel on site. A Load Management Application must be completed before an off-peak meter can be installed.

What qualifies as the electric heat?

Common off-peak setups around Waubun include:

• Electric plenum heaters installed in the ductwork of an existing furnace
• Electric furnaces or electric boilers
• Electric thermal storage units that store heat in bricks during off-peak hours
• Air source heat pumps (usually with a furnace backup), sometimes called dual fuel
• Ground source (geothermal) heat pumps

The co-op also runs efficiency rebate programs. Check their current rebate forms for what qualifies.

The backup heat is the key

Here's the part homeowners sometimes overlook: your backup furnace has to work, every time, on the coldest days of the year. That's exactly when control periods tend to happen. And because the electric heat carries the house most of the time, the backup furnace (usually propane) may sit completely idle for days or weeks, then be asked to start at 20 below.

That pattern produces some very predictable problems:

• Weak igniters that crack or fail on the first cold start after sitting
• Dirty flame sensors that make the furnace light and shut off
• Propane tanks that ran lower than expected, since it's easy to forget about fuel you rarely use
• Switchover wiring or thermostat settings that don't bring the backup on properly when the electric heat is shut off

That's why we recommend a fall tune-up for the backup furnace even if it barely ran last winter. See HVAC Maintenance.

How heat pumps fit in

A cold-climate heat pump can be a good match for off-peak heating. The heat pump runs on the reduced electric rate whenever it's not being controlled, handling a large share of the season efficiently. During control periods, and when it's too cold for the heat pump to keep up, the propane furnace takes over. You end up paying the low off-peak rate for much of your heat and burning propane only when necessary.

Getting this right requires careful setup. The heat pump, the furnace, the thermostat and the co-op's control signal all have to work together, so that the system switches to the furnace during a control period, switches back when it ends, and uses the right switchover temperature in between. When it's configured wrong, you can end up with a heat pump that never gets used, or a house that goes cold during a control period. See Heat Pump Services.

Is off-peak heating worth it?

For many Mahnomen County homes, especially those heating with propane, adding off-peak electric heat can significantly lower the cost of heating. The trade-offs:

• There's an up-front cost for the electric heating equipment, and possibly wiring and meter work
• You must keep a reliable backup system and a supply of backup fuel
• You need to maintain both systems

If you already have a sound propane furnace, adding a plenum heater or a heat pump to use off-peak rates can be one of the more cost-effective heating upgrades available around here.

Common questions we hear

"My house got cold during a control period. What happened?" Usually the backup furnace failed to start (an igniter, flame sensor or propane supply problem), or the switchover isn't wired or configured properly. Call us and we'll find out which.

"Can I use a wood stove as my backup?" Check with the co-op on what qualifies as an acceptable backup. Program rules specify the requirements, and an automatic backup is generally the most reliable choice for your home.

"Do I need a new furnace to join?" Not necessarily. Many homes add off-peak electric heat to an existing furnace in good condition. We'll evaluate your system and tell you honestly whether it's a good candidate.

Get help setting it up

If you're considering off-peak heat, adding a heat pump, or having trouble with an existing setup, call Waubun HVAC Pros at (218) 227-4357. We're based in Waubun, ten miles down Highway 59 from the co-op's Mahnomen headquarters, and we work on these systems all winter.