UC Berkeley economist Severin Borenstein has a really, really great post at the Energy at Haas blog on utility fixed charges to recoup system fixed costs. If you want a primer on volumetric versus two-part pricing, this is a good one. After a very clear and cogent explanation and illustration of the differences among variable costs, customer-specific fixed costs, and system fixed costs, he says
Second, as everyone who studies electricity markets knows (and even much of the energy media have grown to understand), the marginal cost of electricity generation goes up at higher-demand times, and all generation gets paid those high peak prices. That means extra revenue for the baseload plants above their lower marginal cost, and that revenue that can go to pay the fixed costs of those plants, as I discussed in a paper back in 1999. …
The same is not true, however, for distribution costs. Retail prices don’t rise at peak times and create extra revenue that covers fixed costs of distribution. That creates a revenue shortfall that has to be made up somewhere. Likewise, the cost of customer-specific fixed costs don’t get compensated in a system where the volumetric charge for electricity reflects its true marginal cost.
He continues with a good discussion of the lack of a theoretical economic principle informing distribution fixed costs.
I want to take it in another, complementary, direction. The asymmetry he points out is, of course, an artifact of cost-based regulated rate recovery, which means that even under retail competition this challenge will arise, even though his explanation of it is articulated under fixed, regulated rates. And the fact that late night regulated rates are higher than energy costs may not generate a revenue excess that would be sufficient to pay the system fixed costs portion in the way he describes as happening in wholesale markets and transmission fixed costs. This is a thorny problem of cost-based regulation.
Consider a regulated, vertically-integrated distribution utility. This utility offers a menu of contracts — a fixed price, a TOU price, and a real-time price (the attentive among you will notice that this setup approximates what we studied in the GridWise Olympic Peninsula Project). It’s possible, as David Chassin and Ross Guttromson demonstrated, for the utility to find an efficient frontier among these three contract types to maximize expected revenue in aggregate across the groups of customers choosing among those contracts. That’s a situation in which retail revenue does vary, driven especially by the RTP customers, and revenue can be higher to the extent that there’s a core of inelastic retail demand. But they still have to figure out a principle, a rule, a metric, an algorithm for sharing those distribution system fixed costs, or for taking them into account when setting their fixed and TOU prices. And then to be non-discriminatory, they’d probably have to allocate the same system fixed costs to the RTP customers too. So we’re back where we started.
And this is also the case under retail competition. Take, for example, this table of delivery charges in Texas, where the regulated utilities are transmission and distribution wires companies. It breaks them down between customer fixed charges and system fixed charges, but it’s still the same type of scenario as Severin describes.
As long as there’s a component of the value chain that’s cost-recovery regulated, and as long as that component has system-specific and customer-specific fixed costs, this question will have to be part of the analysis.
A related question is whether, or how, the regulated utility will be permitted to provide services that generate new revenue streams that will allow them to cover those costs. That’s a thicket I’ll crawl into another day.