2. ECONOMIC FRAMEWORK

Like many utility operations, there are revenues and costs for street lighting. As the economic climate has generated more awareness of these revenues and costs, industry groups and manufacturers have responded. In particular, the IES has modified its photocontrol selection guide. It now includes a section on economics. The chart below summarizes some of the material in the IES Guide to Selection of Photocontrols, DG-13.

2.1 Revenues

In the United States, the primary source of revenues for utility street lighting is provided by the state tariff. Recently, some utilities are getting new contract revenue from new product offerings, sometimes through an unregulated subsidiary. Some portion of the customer's rate per kilowatt hour reimburses a utility for street lighting. Most often costs to be recovered are calculated based on an assumed number of hours (almost always between 3,700 and 4,300 hours per year; most often between 4,000 hours and 4,200 hours per year). The budget calculations account for the street light population by lamp type, wattages and utilities unmetered cost to provide the energy.

The biggest variable in revenue calculations is the assumption on burning hours. Within continental US and Canada, lowest practical burning hours will be between 4,120 hours and 4,180 hours. If your tariff hours are not in synch with your actual burning hours, you aren't getting paid for the service you deliver. You probably cannot do anything about this in the short term but it's always useful to know where one stands in any negotiation. It's worth asking your rate people.