ENERGY SAVING - 27.11.2009

Should you install low voltage optimisation equipment?

What is it?

Voltage optimisation is a particularly effective means of saving energy because there’s a national problem of over-voltage. This is caused by the supply to most buildings being much higher than the equipment actually needs. This puts a strain on the equipment and generates heat. Savings can be achieved by fitting optimisation equipment to your electrical supply so that the output voltage matches that of the demands of the equipment being used.

Successful trial

After trying out the technology at a few sites, the Environment Agency (EA) has decided to invest in low voltage optimisation technology in 33 of its buildings. It says that it expects to reduce its carbon emissions by around 12% per year - and its energy bill by up to £200,000. At that rate, the EA says the costs of investing in the technology should be recouped within four years. The EA will be following the lead of several other large organisations including DEFRA and Tesco.

Background

The declared electricity supply in the UK is 230 Volts with a tolerance of +/- 10%. This means that on the majority of sites, electrical equipment is running at a voltage much higher than needed, resulting in excessive losses - the optimum voltage for a site is usually lower than the voltage actually supplied.

Principle. This is how voltage optimisation works. The equipment reduces the voltage to the optimum level, e.g. what the equipment actually needs, as opposed to what’s on offer. This in turn, means that less energy is used/wasted.

Double benefit

Low voltage optimisation technology not only filters out excess voltage, it should also increase life expectancy of equipment, particularly lighting. Lamp life expectancy can be reduced by up to 50% by excess voltage, so your maintenance technician could be replacing fewer bulbs if you opt for this technology.

Tip. This equipment doesn’t improve energy efficiency on all types of machinery. So it’s worthwhile carrying out a full investigation and if possible, taking up a free trial, before investing.

How much does it cost?

The cheapest low voltage optimisation equipment is approximately £850. However, this is for a small unit and not suitable for most commercial supplies. The price of the larger units, e.g. the ones being installed by the EA, is much greater. It’s safe to say, that the greater your energy demand, the higher the cost of the unit. However, it’s considered that even with the higher-priced equipment, you should recoup your outlay within five years. Finally, another significant downside of the technology may be the space you need to install it and the floor strength required.

Note. The amount of space required for low voltage optimisation equipment ranges from 0.5m² to about 2m². It’s also heavy, most units weigh 100kg to 1,200kg. The equipment needs to be positioned so as to take the incoming supply and feed it to the distribution board.

For further information on low voltage optimisation equipment, visit http://environment.indicator.co.uk (EN 04.06.03).