Most of what is discussed here involves lowing energy costs for residential customers, hence the name HOME energy pros. The commercial customer has a monthly energy bill that often exceeds the amount of energy used in a YEAR for a personal residence. Are we missing the big fish, the commercial side?
Demand charges make up a large portion of a commercial account's total bill. Reducing peak demand or simply shifting use could save a commercial customer thousands of dollars per year. Since peak demand is often at the same time at maximum solar output, payback times might be significantly shorter than residential. It's a different ball game, but is it worth playing?
Commercial is another kettle of fish & unless you are an engineer the chances of breaking into the market are difficult. While resi is primarily worried about the envelope, most commercial work is focused on lighting, motors, pumps, etc...
It seems to me that Sean and Bob are both right. I eventually hope to tap into the light commercial business, where the major difference from residential may be lighting, and having a buddy or two in the commercial HVAC arena. There are a lot of small offices in the world these days. In this area, they are often former residential buildings-historical buildings that may house offices for doctor$ and lawyer$. Of these, the adjustment may be quite simple, although it would be smart to know ADA requirements (access requirements, trip hazards, etc.) and other bells & whistles to justify the higher premium for an audit and to be a trusted source (if not an actual expert in those areas) over time.
Many others are flex-warehouses. Considering the construction of many flex-warehouses, a commercial glass company may be on your speed dial for installing vestibules & I.G. panes(on the warehouse side) to help isolate the indoor climate from both the warehouse & the exterior. But access for airsealing & improved insulation may often be very easy as there is often a +/- 10 ft clearance between office ceilings & warehouse roofs. I would tread with caution in approaching flex-warehouse spaces; long-standing occupant habits may cause some disappointing results.
In both areas, you may see a lot more air sealing challenges due to the need for cabling, etc. And, of course; watch out for the ceiling tiles!
If you are a lone ranger on the resi side, it may be difficult to go alone on commercial jobs, and you may find yourself working a lot of weekends. For these reasons, and considering the peak usage payback, etc., it may be a good way to increase your monthly take-home. $1500-2500 is a lot easier for a Dr. or a snake in the gra,,,,uh,,,lawyer to swallow than $400-500 for a homeowner. I'll gladly work nights or weekends for that bump.