Sauk County Solar Generating System

Kilo-watts (kW) and Kilo-watt hours (kWh) are measures of electrical capacity and energy production. A kW is a measure of instantaneous capacity. A 10 kW solar PV system running at full capacity for one hour will produce 10 kWh which is a measure of energy or electricity production. The cost of energy delivered is measured in cents per kWh. Most Sauk County residents buy electricity from an electric utility at a price of about 12 cents per kWh.

In both the above locations, the PV systems will offset 15-20% of the electricity used by the Centers. This level of production was chosen to maximize the financial savings to the County and minimize the amount of electricity production that would be sold back to the utility at any point in time. The utility will only pay the much lower wholesale price of 2.5 to 4.2 cents per kWh depending on the time of day for excess electricity sold back to the utility.  Batteries are not yet financially feasible for storing electricity for later use.   

Neither PV system directly heats water or air.

Sauk County’s initial investment was minimal due to a Focus on Energy rebate and third party financing. The County’s solar PV systems are sized to be cash flow positive, i.e. payments over the course of the year to third party investors are less than the cost savings from reduced purchases of electricity from the serving utilities. The county has the option to buy-out the solar PV systems in future years, which would then provide larger cost savings to the County. The solar PV systems are reducing the carbon footprint of Sauk County Government by about 725 tons per year.