Sub-metering reveals highs and lows of play time…
When energy managers at a leisure provider wanted to identify wasteful use of electricity they called in specialist sub-metering company Sinergy to fit portable energy loggers to more than 40 distribution transformers. Sinergy was called in to survey electrical demand/usage over four weeks at several of the leisure providers sites, which included family fun pools, restaurants and accommodation.
The company was particularly interested in identifying savings from peak lopping and overnight wastage elimination. Load current on the distribution transformers was measured via outgoing cables. Sinergy e-Trackers were magnetically clamped to transformer casings, with their flexible CTs long enough to span the parallel conductors in parallel pairs or sets of three or four.
A three phase voltage measurement reference was taken via Sinergy’s EV-TRAC synthesizer, which plugs into a single phase socket and has an electrostatic phase identity feature essential in this style of measurement. Deltrax software produced demand profile graphs, with daily and weekly graphs of multi and single parameter graphics. The survey results were dramatic, with a peak demand of more than 500kW (level A) and heavy daytime consumption (level B). Night time demand did not fall as low as may have been expected but the survey did highlight frequent short dips which, if extended for a full eight hours overnight, could deliver power savings of some 7,000 kWh per week equating to more than £3,000 over the summer alone.
Furthermore, the peak demand of 500kW had a significant effect on the site’s monthly Maximum Demand charge and annual Capacity Charge. These two elements can represent up to 25% of an electricity bill. The question was whether peak demands at other distribution transformers coincided to push the 500kW level two or three times higher. The Excel uplink within e-Tracker’s Deltrax software package enables cumulative additions and comparisons with other sites to be made.
Sub-metering for fast efficient energy cost reductionsS
Both fixed sub-metering systems with automatic data collection and portable profile recorders take their place in the forefront of the continuing battle to reduce energy costs. The latter, with its superb non-invasive operational characteristics, is very often the starting point in the determination of the cost reduction strategy. Sinergy sub-metering systems are intended to identify how much power is being used when and where. At the end of a monitoring period we provide a complete report on the findings but do not suggest ways of making improvements, that’s up to facility/energy managers.