Commercial Buildings Waste Energy Too
The efficiency-first principle that applies to residential solar applies equally to commercial buildings. A business with an inefficient HVAC system, poor building insulation, outdated lighting, or operational energy waste will pay more for solar than necessary — because the system gets sized around a load that's higher than it needs to be.
For small and medium-sized business owners, reducing energy costs before installing solar isn't just good practice — it's often the difference between a commercial solar project that makes clear financial sense and one that's borderline.
Where Commercial Buildings Waste the Most Energy
HVAC Systems
Heating, ventilation, and air conditioning typically accounts for the largest portion of a commercial building's energy use. Older HVAC equipment running below rated efficiency, poorly maintained systems, or systems that are oversized or undersized for the space all drive energy costs up. A commercial HVAC assessment can identify whether replacement or a tune-up makes sense before solar is sized.
Lighting
For many commercial buildings — particularly retail, office, and warehouse spaces — lighting is a significant energy load. If your building still uses fluorescent T8 or T12 fixtures, or older HID lighting in warehouse applications, an LED retrofit can reduce lighting energy use dramatically. The ROI on commercial LED retrofits is typically very strong, often with paybacks of 2–4 years.
Building Envelope
Commercial buildings with poor roof insulation, single-pane windows, or air leaks through the building envelope require more energy to maintain comfortable conditions. Commercial energy audits frequently identify building envelope issues that — when addressed — reduce HVAC loads significantly.
Operational Practices
Lighting controls, HVAC scheduling, and equipment management practices can reduce energy consumption without any capital investment. A commercial energy audit typically identifies operational changes alongside equipment and building improvements.
The Commercial Energy Audit
A commercial energy audit evaluates your building's energy use across all major systems. ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) defines three levels of energy audit with increasing depth. For most small to medium commercial properties, an ASHRAE Level 1 or Level 2 audit provides a practical foundation for investment decisions.
The audit should produce prioritized recommendations with estimated costs and savings, so you can evaluate each measure before committing to any project.
The Right Sequence
- Commission a commercial energy audit
- Implement the highest-ROI measures: typically LED lighting and HVAC controls/scheduling
- Evaluate larger investments: HVAC replacement, building envelope upgrades, heat pumps, geothermal
- Size commercial solar around the post-efficiency electrical load
When Efficiency Measures Pay Back Faster Than Solar
LED lighting retrofits, HVAC controls, and air sealing frequently have payback periods shorter than commercial solar. For businesses managing cash flow carefully, addressing these lower-cost, faster-payback items first frees capital for the larger solar investment — and reduces the size and cost of that solar investment.
Frequently Asked Questions
Does SPM offer commercial energy audits?
SPM evaluates commercial properties as part of the commercial solar and energy services consultation process. Contact us to discuss your building's specific situation.
Are there utility programs for commercial efficiency in Illinois?
ComEd and other Illinois utilities have offered commercial energy efficiency programs with rebates on qualifying equipment and sometimes subsidized audit services. Program availability and terms change over time — verify current offerings directly with your utility.
Ready to evaluate your commercial building's energy profile? Learn about SPM's commercial services or schedule a commercial energy review.