Had a situation with a cold storage facility in Akron on Ohio Edison. The client's demand was averaging 480 kW which put them solidly in the Large General Service rate — or so I thought. The tariff has a footnote in the eligibility section that says customers with demand between 400 kW and 500 kW may elect either the General Service or Large General Service rate, whichever is more favorable. The utility had defaulted them to GS when LGS was cheaper by $2,100/month. Nobody at the utility knew about the election provision. I had to show them their own tariff.
Rate schedule eligibility — the fine print that changes everything
The election provisions are audit gold. PSE&G in New Jersey has a similar overlap zone between their General Lighting and Power rate and their Large Power and Lighting rate. The overlap is between 500 kW and 750 kW demand. I found 8 accounts across three clients that were in the overlap zone and on the less favorable rate. Combined savings were over $9,000/month. The utility had no idea — the customer service reps I spoke to didn't know the overlap existed until I showed them the tariff page.
Election provisions, overlap zones, and conditional eligibility criteria are among the most profitable findings in utility bill auditing. They exist because rate designers need to create smooth transitions between rate classes, but the billing systems are usually programmed with hard cutoffs. The tariff says "may elect" but the billing system only assigns one rate based on a single threshold. This is why reading the tariff yourself is essential — you cannot rely on the utility to place your client on the optimal rate. They place clients on the default rate. Your job is to determine if a better option exists.
Another fine print item to watch for: seasonal rates. Some tariffs have summer and winter rate schedules with different eligibility criteria. A client might qualify for a more favorable rate in winter months even if they don't qualify in summer. Some utilities allow seasonal rate switching and some don't — it depends on the tariff language. I found a resort in Asheville on Duke Energy Progress that could switch to a lower rate from October through April based on their reduced winter demand. Saved them $1,400/month for 7 months per year.
Great point about seasonal eligibility. I need to start checking that more carefully. Most of my clients are steady-load industrial so it hasn't come up much, but my newer commercial clients definitely have seasonal patterns.