By Jerry Bernstein, Renewable Energy/Special Projects Coordinator
This planet is our only home and many congregations of all faiths, Interfaith Power and Light (IPL) members and non-members, are committed to safeguarding it for the present and future generations. Two common congregational efforts we’ve seen to reduce carbon emissions include improving the energy efficiency of existing operations and replacing fossil-fuel generated electricity with a solar photovoltaic (PV) system.
While Solar PV systems are visible and cost-effective in many locations, the phrase “reduce then produce” remains relevant. In our experience, we’ve found energy efficiency improvements such as LED lighting systems have 1 ½ – to 3-year payback (i.e., cost-recovery) periods where solar photovoltaic (PV) systems require a 6- to 10-year payback. This blog provides a few comments on both.
Energy Efficiency Improvements
While each location will be different, a general idea can be gained from national averages (see Figure 1, below). Clearly Heating, ventilating and air conditioning (cooling) collectively known as HVAC are significant! As each congregation is unique, an Energy Audit is a useful first step to determine your specific consumption (and carbon emission) pattern. Unfortunately, this logical and appropriate first step is perhaps the most confusing and misunderstood as all audits are not equal.

“Free” audits are often available (typically Benchmarking (comparing your bills to other similar buildings) or Benchmarking + quick walkthrough), but these provide the least actionable information. Exceptions may exist if a local utility or non-profit is funded to provide a more thorough audit at reduced or no cost to the recipient. Comprehensive audits can cost hundreds of dollars and involve analysis of your installed equipment and a cost analysis of alternatives. An auditor’s affiliation with the Building Performance Institute (BPI) or American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) should be a plus. Home Energy Rating System (HERS)-qualified auditors can be useful if your building(s) are not much more complex than a standard residential structure.
In our experience, HVAC changes can have the greatest impact, but these are usually pursued only when the existing heating or cooling system needs replacement. Lighting changes, however, appear to be so favorable that these can be implemented at any time; numerous IPL Cool Congregation Challenge winners are congregations that have measurably reduced costs by replacing existing lighting with LED systems. Smaller changes, like changing the set-point on water heaters can have lesser, but measurable impact at no cost.
Renewable Energy (Solar PV) Projects
Over 1000 congregations of all faith traditions in the United States have installed solar PV systems to provide electricity and as a visible statement of faith and stewardship. As to whether a PV system financially benefits a particular congregation, the answer is “it depends.” Each congregation’s unique costs and savings need to be compared. It is much easier to financial justify a PV system in a location with high average electricity costs such as Hawaii, California, and the Northeastern states than if costs are at or below the national average. As example, electricity in California (300 congregations with PV systems) and Massachusetts (100) averages 17 – 18¢ per kilowatt hour (kWh); conversely, electricity in Louisiana (1) and Oklahoma (2) averages less than 8¢ per kWh. State policies also influence the viability of a solar PV system; installation costs vary, but not greatly, nationwide.
Installing a PV system is not synonymous with “Fund Raising.” Hundreds of congregations have found ways to finance PV systems over time, resulting in monthly and annual savings typically with no front-end costs. These savings provide flexibility to constrained budgets and free funds for other congregational needs. These financing options allow for payments over time—spreading the cost over 5, 10 or up to 25 years. In IPL’s national experience, there are four major methods by which congregations fund PV systems, including outright purchase, leasing the system (numerous variants, including congregant leases), entering into a power purchase agreement (PPA), or financing through a Property-Assessed Clean Energy (PACE) loan; not all of these are allowed in all states.
How do you know if the PV system is a good investment? Compare your PV acquisition costs (plus any supplemental electricity purchased from your utility) with the expected cost of continued utility-purchased electricity for the next 20 years (or appropriate analysis period). Any PV installer who provides a proposal should include this analysis as part of their bid.
There are many ways to go “Green;” two common ones have been described. They do require some effort, but IPL affiliates (and National) are available to provide advice and suggestions.
Visit our Cool Congregations page for resources on reducing emissions at congregations.

(Photo courtesy of Nicholas Kittleson)