Every household is different. Key variables include:

• How much energy is used during off-peak and on-peak hours
• Amount of solar generation installed
• Orientation of the solar array(s) on your home
• Fuel used for primary heating in your home

TOD pricing provides solar credits for energy that isn’t immediately used in your home, which flows back into the grid. The on-peak rate for generation credits is at least three times the off-peak credit rate. Energy charges reflect a similar difference between on-peak and off-peak rates. For details: TOD – Pricing and TOD Pricing – Solar Customers.

The graph below shows the monthly bills for an average Fort Collins residential customer (without solar) who uses gas to heat their home – approximately 7,700 kWh per year. In this example, the customer proposes to add a 6-kW solar system facing south, which will generate approximately 8,900 kWh (115 percent of the load).

While all residential customers can benefit from reducing or shifting a portion of their energy use from the on-peak hours, only customers with renewable generation can benefit from pushing power back to the grid during on-peak hours. If you can use less energy than you generate during on-peak hours, you can sell excess solar power back to the grid at the higher on-peak price.

Reduce your use and costs:

1. Reduce your overall electric use.
2. Shift electric use to off-peak times of the day or week.
3. Upgrade or replace energy using equipment or appliances to ENERGY STAR®.

In the example below, the average Fort Collins household bill is shown with power supplied by a 6-kW solar array. The graph illustrates that conserving 10 percent of on-peak energy use plus shifting another 10 percent of energy use from on-peak to off-peak times saves a customer with an average size solar system $60/year, or an average of $5/month.

Did you know that the amount of energy generated by a solar array over the course of a year varies depending on the direction it is pointed? If weather was not a factor, a solar array would generate the most energy facing south. However, Fort Collins weather tends to have a higher likelihood of heavy clouds in the afternoon. Because of the influence of higher value for generation under the Time-of-Day (TOD) pricing on-peak periods, people have asked whether solar systems should be oriented more to the west to capture more generation during those on-peak hours.

Fort Collins Utilities’ analysis of solar production value under TOD pricing shows that south (180 degrees) is still the best orientation to maximize the financial value of energy generated by a solar system.

Customers who install a battery storage system can store excess solar energy generated during off-peak hours and discharge the battery during on-peak hours. The battery can be discharged to serve energy loads in the home and can also be discharged to the grid to generate net metering credits.

This can be beneficial because excess solar production sold back into the grid during the off-peak hours of the day is valued at off-peak rates, roughly 6 cents/kWh. If that energy is stored until the on-peak period and discharged, it is worth more than 3 times as much - roughly 20 cents/kWh.

• Colorado Solar & Storage Association:
  (COSSA)
• Home energy efficiency and solar:
  National Renewable Energy Lab’s Solar Energy Basics

Residential solar PV system size is limited to either 12 kilowatts or to one that produces no more than 200% of your average annual energy load (based on a 24-month period), including all dedicated generation sources. For solar systems that are not owned by the property owner, such as leased systems, maximum solar system sizing is limited to 120% of intended renewable energy offset. 

Do-it-yourself projects are allowed, but are not eligible for rebates.

If you already have a solar PV system and are considering a possible expansion, contact us before working with solar contractors on designs so that we can evaluate how much solar you could add within the maximum size limits.

We will need a copy of your solar generation report for the past 12 months (typically available through your inverter or solar contractor) in order to assess the maximum allowable expansion of your solar system. That data allows us to understand your total PV system production and to calculate your total energy consumption on-site. You’ll be allowed to expand your PV array so the total combined production of the existing generation and new array does not exceed 12 kW, or if larger than 12 kW, 200% of your total annual electricity consumption.

You and solar contractors can use this data, along with your solar production data, to model your total energy use and develop an accurate projection of what your energy costs. We recommend that you have contractors model your projected savings using the Time-of-Day pricing now active in Fort Collins.

Utilities uses the following formulas to establish an allowed solar expansion limit based on annual data:

• Solar Self-Consumption (kWh) = (Total Solar Production) – (Energy Returned to the grid)
• Total Energy Consumption (kWh) = (Solar Self-Consumption) + (Energy Delivered from the grid)
• Max Solar Production Limit (kWh) = 200% * (Average Annual Energy Consumption)
• Solar Addition Limit (kWh) = (Max Solar Production Limit) – (Total Annual Production of existing PV array)

*The time periods for solar production and metered energy consumption and returned should be aligned to calculate these values accurately. By selecting longer time periods of 1-2 years for analysis, the alignment between monthly inverter reporting and billing cycle dates are reduced to negligible variation. Utilities typically calculates Average Annual Energy Consumption based on 24 months of billed data.

Yes. Your system must be grid-tied, and you must be a Fort Collins Utilities electric customer.

Even with rebates and tax incentives, PV systems can take years to pay for themselves. Consult your solar contractor for a payback estimate.

Applications may be accepted for systems that don't completely conform to performance guidelines at a prorated rebate level in order to account for the reduced performance. Fort Collins Utilities reserves the right to exclude systems that are likely to perform substantially below the program guidelines.

Fort Collins Utilities' rebate includes the purchase of the RECs associated with your system helping with compliance with the State of Colorado Renewable Energy Standard and the community's Energy Policy and CAP goals. Commercial rebates for systems greater than 20 kW may have their RECs retired on their behalf by the City of Fort Collins.

The program is intended to provide year-round access to rebate funding for all eligible applicants. We may adjust the rebate amount per customer as needed to provide funding stability.

Only newly installed PV systems are eligible.

The cost of a solar PV system installation continues to decline. In 2018, the average cost for residential PV systems without battery storage in Fort Collins was approximately $3.60/watt-DC. With an average system size of 6 kW-DC, that means the average system cost is approximately $21,800.

At a national level, the average residential PV system installed cost was at $2.89/watt-DC at the end of Q2 2018, according to Wood Mackenzie, Ltd. / SEIA U.S. Solar Market Insight.

Oversizing solar PV systems can present a financial risk to the customer. Fort Collins Utilities does not pay customers for accumulated credits from solar generation unless all the following criteria are met:

1. The net credit on the account exceeds $300 on March 1;
2. The net metering account has been active for longer than 1 year; and
3. The customer does not receive all standard services from Fort Collins Utilities. This is because any excess credits from electricity generation are applied toward other utility (water, stormwater, wastewater) bills.

Customers who already have received a rebate on an existing solar installation are eligible to receive a second rebate for additional solar and battery storage at the same address.