HERE’S SOMETHING you might not know: the declared electricity supply in the UK is 230 volts with a tolerance of ±10%. Yet the voltage supplied to you will typically be around 245V. Most appliances will work more efficiently and use less electricity at a much lower voltage. This means that on most sites, electrical equipment is running at a voltage much higher than needed, causing losses.
VOLTAGE OPTIMISATION devices maintain the supply at 220V. That equates to about a 10% reduction in energy use. By eradicating the usual peaks and troughs of supply, they can also increase the life expectancy of equipment, particularly lighting. Lamp life expectancy can be reduced by up to 50% by excess voltage. Optimisation means fewer lightbulbs and less time spent changing them.
AS WITH many sustainability initiatives, the savings are not guaranteed. One government study showed returns ranging from a 19% saving to a 4% loss. It depends on the premises, your equipment and what it’s used for. Manufacturers can provide estimated savings and, in time, energy bills can be compared, but for those wanting to know exact savings there are devices such as iVolt which show actual energy use with and without voltage optimisation.
THERE’S A cost to consider and these devices aren’t cheap. For smaller premises optimisers are available for around £3-4,000 but on large sites the costs can escalate to tens of thousands. There are plenty of case studies with figures and data on the savings, but very few showing the initial capital investment.
£15,500 and counting
FOXHILLS HOTEL and Resort adopted the technology a couple of years ago and energy bills at the 70-room hotel have been cut by £15,500 a year. Given that the annual bills are in the region of £156,000 that’s not bad. “The savings are threefold, really,” says the facilities director, Ben Biggs. “It not only saves us money by reducing the amount of power we use but it reduces the strain on equipment, which means it lasts longer, and by monitoring our energy consumption in real time it provides me with crucial information which I can then take to my staff to make them more conscious of the electricity we’re using – and in many cases wasting.” Another hotel in North Yorkshire is expecting to save £7,900 a year on energy bills (and cut carbon emissions by 65.7 tonnes) having invested £39,500 in voltage optimisation. Whitbread has also invested in the technology, with early data showing savings as high as 18% on some sites. There are also devices across government sites and the Environment Agency says it is saving an average of 8% and up to 17% in some buildings.
One more thing
THE AMOUNT of space required for low voltage optimisation equipment ranges from 0.5 sq. m to about 2 sq. m. It’s also heavy – most units weigh 100-1,200kg. So, if you are planning to expand and anticipate that your electrical demand will increase then tell the installer, as they will have to allow more headroom by installing a larger unit.
If you rent your premises anything you do needs to have the backing of the landlord and, given the returns on investment, you need to be sure you are not going anywhere any time soon. This will add value to the premises.
Many manufacturers have cost savings calculators, which allow you to input your equipment and see the savings available. However, you need to do a full assessment of your energy use and demands before considering such a big investment. This should be carried out – often for free – by the installer.