Tiverton High School : Bandvulc Tyres : The Environment Agency : Devon County Council : The Eden Project : DML

Tiverton High School is located on the outskirts of Tiverton, Devon. It is a mixed, 11 to 18 comprehensive school with 1,000 students. “This system is all part of our approach to our environmental principles and part of our belief that we should practise what we teach,” says Acting Head Teacher Mr Kaye. “This case study examines the benefits to the school of measuring its gas, electricity and water supplies with ½ hourly remotely read meters.

“Thanks to the enthusiasm of its Bursar, Steve Downe, the school already had thelowest electricity use per pupil in the county. It has built on that by achieving substantial reductions in gas and water usage. The school has:

• Saved approximately £24,000 p.a.
• Improved heating efficiency.
• Identified and isolated a water leak from an underground pipe serving three outbuildings that were no longer used.
• Identified a heating control fault that may be occurring in other Devon County schools.
• Reduced electrical power consumption.

"Like most secondary schools, Tiverton School only had access to 30 minute data for its electricity consumption, and then only up to a month after the event. There was no way to obtain detailed profile data for
gas and water, or information about the outside air temperature and other factors that were driving variations in energy consumption.”

A meter reading system was installed in February 2004, during school hours, with no disruption to normal activities. The system reports through a software package on Steve Downe’s PC, and can also be dialled up
remotely.

School hours are 9am to 4pm, with additional evening and weekend use of certain rooms. Cleaners and maintenance staff are in the building from 8am to 7pm. The school is closed for 13 weeks of the year.

ENERGY SAVINGS IDENTIFICATION

“The system immediately showed a baseline water consumption of 900 litres per hour. This warranted a more thorough investigation, and the leak was traced to an underground pipe serving three prefabricated classrooms. Only one of the three was still in use, and that one had no need for running water. The annual water cost saving was £20,000, with annual carbon savings of 3,469 kg.

"With the start of the new heating season in September 2004, we discovered that the control system was starting the main boilers at midnight or earlier, to warm the school up for the following day. The fault was found to be on an ‘optimum start-stop’ controller”. The controller was turned off and restarted, and the heating ran for six hours less per day – but within a few days the fault recurred. To investigate the fault further, the school purchased another radio transmitter with an embedded temperature sensor. Mr Downe then placed it overnight at various locations around the school, to record how long it actually took to reach a comfortable temperature. This showed that the heating did not need to start any earlier than 6am, even in the depths of winter. Heating has therefore been put on a fixed time schedule, pending a permanent fix for the optimum start-stop fault.

THE FINANCIAL CASE
Annual water cost saving was 7,884 cubic metres, saving £20,000 and 3,469 kg CO2 per annum. Annual gas saving was 216,000 kWH, worth £3,456 and 41,000 kg of CO2 annually.

The total cost of the original meter reading system was £5,075 and the additional transmitter cost £180. The system has paid for itself in three months on water savings alone.