Last month the California Public Utilities Commission (CPUC) issued a decision in Phase II of the PG&E 2020 General Rate Case that endorsed all but one of my proposals on behalf of the Agricultural Energy Consumers Association (AECA) to better align revenue allocation with a rational approach to using marginal costs. Most importantly the CPUC agreed with my observation that the energy system is changing too rapidly to adopt a permanent set of rate setting principles as PG&E had advocated for. For now, we will continue to explore options as relationships among customers, utilities and other providers evolve.

At the heart of the matter is the economic principle that prices are set most efficiently when they adhere to the marginal cost or the cost of producing the last unit of a good or service. In a “standard” market, marginal costs are usually higher than the average cost so a producing firm generates a profit with each sale. For utilities, this is often not true–the average costs are higher than the marginal costs, so we need a means of allocating those additional costs to ensure that the utilities continue to be viable entities. California uses a “second-best” economic method called “Ramsey pricing” that applies relative marginal costs to serve different customers to allocate revenue responsibility.

I made four key proposals on how to apply marginal cost principles for rate setting purposes:

1. Proposes an updated agricultural load forecasting method that is more accurate and incorporates only public data and currently known variables that can predict next year’s load more accurately.
2. Use PCIA exit fee market price benchmarks (MPBs) to give consistent revenue allocation across rate classes and bundled vs departed customers.
   1. Include renewable energy credits (REC) in the marginal energy costs (MEC) to reflect incremental RPS acquisition and consistency with the PCIA MPB.
   2. Use the resource adequacy (RA) MPB for setting the marginal generation capacity cost (MGCC) due to uncertainty about resource type for capacity and for consistency with the PCIA MPB.
3. Marginal customer access costs (MCAC) should be calculated by using the depreciated replacement cost for existing services (RCNLD), and new services costs added for the new customers added as growth.

PG&E settled with AECA on the first to change its agricultural load forecasting methodology in upcoming proceedings. The CPUC agreed with AECA’s positions on two of the other three (RECs in the MEC, and MCAC). And on the third related to MGCC, the adopted position differed little materially.

The most surprising was the choice to use the RCNLD costs for existing customer connections. The debate over how to calculate the MCAC has raged for three decades. Industrial customers preferred valuing all connections, new and existing, at the cost of new connection using the “real economic carrying cost” (RECC) method. This is most consistent with a simple reading of marginal cost pricing principles. On the other side, residential customer advocates claimed that existing connections were sunk costs and have a value of zero for determining marginal, inventing the “new customer only” (NCO) method. I explained in my testimony that the RECC method fails to account for the reduced value of aging connections, but that those connections have value in the market place through house prices, just as a swimming pool or a bathroom remodel adds value. The diminished value of those connections can be approximated using the depreciation schedules that PG&E applies to determine its capital-related revenue requirements. The CPUC has used the RCNLD method to set the value for the sale of PG&E assets to municipal utilities.

The CPUC agreed with this approach which essentially is a compromise between the RECC and NCO method. The RCNLD acknowledges the fundamental points of both methods–that existing customer connections represent an opportunity value for customers but those connections do not have the same value as new ones.