New carbon footprint calculator

The calculator shows how much the carbon footprint can be cut back by reducing the speed of electric motors with variable speed drives. “There are already many carbon calculators around but none, as far as we know, that addresses this huge area of energy use. The possible savings can be very substantial – reducing the speed of motors with variable speed drives can frequently save over 50% of the energy used and in extreme cases by as much as 90%, without any detriment to the application.” says Steve Ruddell, general manager, drives and motors, at ABB. An estimated 11 million motors, with a total capacity of 90GW, are installed in UK industry. On an average industrial site, motor systems account for two thirds of the electricity used. They are responsible for about 40% of the UK's total electricity consumption. “Quantifying the carbon footprint helps organisations manage their footprint and reduce emissions over time. But motor energy use is frequently overlooked, despite being the largest area of electricity use in industry. Our new calculator aims to plug a huge gap in the market,” Ruddell says. The calculator lets the user know how much their carbon footprint could be reduced by equipping a particular motor with a variable speed drive. The motor rating is defined by the user. The calculator shows the energy savings in kWh, the monetary savings, the CO2 savings, the cost of a suitable drive and the payback time. Ruddell says one customer installed drives on two pumps, replacing two fixed-speed starters. The motors were rated at 30 kW but once under drive control, the energy used was only 6.7 kW. Electricity costs, originally £18,000 annually, were reduced by 75% or £13,600. As the drives cost £9,000 to purchase, payback was seven and a half months. This installation saves 80.17 tonnes of CO2 per year, equivalent to flying back and forth from London to New York 62 times or driving 309,000 miles per year. The carbon footprint calculator is available at www.abb.co.uk/energy, as an online application.