Addressing Electricity Demand at Alliant Energy Center

A major Madison landmark, the Alliant Energy Center draws numerous events throughout the year, including several animal shows at its two livestock pavilions. Some of these shows cause a big jump in electricity demand from the equipment that participants bring into the pavilions, including mini fridges, microwaves, hair dryers, space heaters, and fans. This leads to high electrical costs for Dane County because commercial spaces are charged an additional fee for their instantaneous power consumption at any given time, as opposed to residential customers who have a consistent rate regardless of day-to-day consumption differences. Because these facilities are only used 130-150 days of the year, the Dane County Office of Energy & Climate Change asked EAP students Drashti Amin, Ugo Ikegwu, Erik Tillman, and Javiera Vergara to evaluate solutions to combat this spiky and intermittent demand, with the goal of lowering costs and emissions.

The group began by analyzing the pavilion’s electricity demand and evaluating the cost of events taking place. They found that energy costs stemming from events account for 48% of the total electricity bill, and that a single event with a high peak in demand imposes costs for the next 12 months. The alternative technologies to reduce these peaks the group considered included a diesel generator, natural gas generator, solar photovoltaics (solar panels) plus  battery storage, and to continue using the grid. In estimating the emissions associated with each technology, students determined that the solar PV plus battery and natural gas generator were the most viable options. The solar PV plus battery had a high investment cost, and a large capacity battery was needed to fully shave the peaks down. The natural gas generator had a lower investment cost but was also dependent on fuel cost when running, resulting in a payback period of roughly 11 years. Because the solar and battery system required a very high upfront cost and thus a long payback period, the natural gas generator proved to be more cost-effective in the short term. However, the solar and battery system offered more emissions savings, though the natural gas generator had similar emissions to the electricity from the present-day grid. If implemented, the natural gas generator would save an estimated $145,000 per year.