Following the mandatory energy usage audits recently carried out by qualified assessors as part of the Environment Agency’s Energy Savings Opportunity Scheme (ESOS), voltage optimisation emerged as one of the technologies most regularly recommended to companies as a viable solution to reduce energy consumption levels.
This article explains why, on the back of the recent ESOS audits, it is important that facilities managers fully understand the role voltage optimisation can play in their sustainability strategies.
Voltage optimisation is a well-established and highly effective method of reducing a company’s energy consumption, decreasing its carbon footprint and producing savings on electricity bills.
The concept behind the technology is simple. On the whole, power is supplied at a higher voltage than is necessary. Although the ideal voltage required for most electrical equipment in the UK is 220V, the average delivered is actually 242V – voltage can be delivered at levels as high as 253V. The mismatch between voltage required and voltage delivered results in a waste of energy and of course money. Voltage optimisation corrects the over-voltage and brings it in line with the actual needs of the equipment on site, through use of a device installed in series with the mains electricity supply.
High Voltage (HV) side optimisation technologies offer optimisation solutions to sites that own their own distribution transformers. Many technologies exist, but there is only one system currently on the market that provides HV, electronic variable voltage optimisation. This is a combined solution that replaces an inefficient on-site HV transformer with an amorphous core super-low loss HV transformer, with integrated electronic-dynamic voltage optimisation technology.
Depending on the age and type of the transformer that it replaces, an amorphous core transformer can provide between 1% to 5% savings simply because it is so much more efficient. In addition to savings on replacement of the transformer, the integrated voltage optimisation technology can be expected to provide further savings of anywhere between 12% and 15%.
Low Voltage (LV) side optimisation is connected to the low voltage side of a building.
There are two variations of LV side optimisation technology available: fixed and variable (also known as electronic-dynamic, electronic or intelligent voltage optimisation). Fixed voltage optimisation systems reduce the incoming voltage by a set amount to the optimum level for site operations. However, output varies as the input voltage differs.
Variable voltage optimisation systems set the output voltage at the optimum level and maintain this by systematically managing the peaks and troughs in the power supplied, irrespective of the incoming voltage levels, to ensure that voltage is supplied at a constant, stable level.
Voltage optimisation provides savings on a variety of loads but not all equipment will consume less energy. The greatest savings come from inductive loads such as lighting and motors, especially if motors are not always loaded at 100% of their capacity. A building that has fixed speed devices such as air-handling units, multi stage compressors (i.e. chillers), pumps and standard switch-start fluorescent fittings, will achieve high savings.
Some loads such as VSDs will also see savings but at reduced levels and some loads will yield zero savings but will benefit in other ways. It is important to understand the electrical loading characteristics of your site and to remember that no two sites are the same.
All sectors can profit from voltage optimisation technology – from hospitals that need to maintain a steady power delivery 24 hours a day to operate sensitive, multi-million pound equipment, to government buildings, hotels, supermarkets and warehouses that are keeping a keen eye on energy expenditure and carbon emissions in order to meet sustainability targets.
The manufacturing industry particularly benefits from its ability to lower the operating temperatures of motors, thus reducing maintenance costs.
There is no downside to voltage optimisation. It can be used in conjunction with other sustainable technologies such as solar or wind power, and pays for itself within three years. After that, the substantial savings are enduring and feed straight back to a business’s bottom line.
Designed, engineered and manufactured in the UK since 2002, Powerstar is the market leading voltage optimisation brand. Powerstar systems are able to deliver substantial reductions in energy consumption through fixed or electronic-dynamic optimisation at either the HV side (High Voltage) or LV side (Low Voltage) of a site without impacting on the business operations of the building itself.
Having worked with an impressive portfolio of blue chip clients, government departments and a range of SMEs the Powerstar team are industry experts in voltage optimisation, able to provide advice and guidance to facilities managers looking to implement voltage optimisation on the back of ESOS audit recommendations for their sites.More