Record, report, and reduce

Industrial and commercial energy use has been thrown into sharp focus by the introduction of the Carbon Reduction Commitment, which demands that all facilities falling under its remit record, register and cut their energy bills.

The deadline for registration has passed and theoretically participants will now be meticulously monitoring their half-hourly electricity consumption in readiness for purchasing carbon allowances next April. Or maybe not. Research suggests that almost 75% of business leaders questioned were unsure if their organisation should be registering – a worrying statistic at such a critical point.

However, once the scheme beds down concern has to switch from recording and reporting energy use to actually reducing it, and this is where the challenge lies for business operations. Complying with CRC requires a long-term plan that introduces energy saving solutions year after year and it will be a fine balance between financial and environmental demands. There are a range of power saving initiatives that can be introduced throughout commercial premises, factories, schools, hospitals, leisure centres etc. Some are more straight forward than others, for example a London hospital trust cut its energy bill by approximately £500,000 simply by asking staff to turn off lights and shut down electrical equipment as appropriate. Other companies, Marshall Tufflex Energy Management included, have installed lighting systems activated by movement sensors to ensure lights do not burn bright into the night.

But for a number of companies registered for CRC there will come a point when only a ‘big ticket’ investment will deliver the required results. And that’s where we believe voltage optimisation will come into its own simply because it can cut power bills by 15% to 25% (and carbon emissions by approximately the same percentage), has a short pay-back period and is relatively straight-forward to retrofit. Many of our clients are eligible for 0% Carbon Trust loans so there is no cash outlay required, making VO a cost-neutral investment that cuts hundreds of thousands of pounds off electricity bills.

In basic terms, voltage optimisation systems are an interface between the main electrical feed and the facility they serve. In many areas of the world, including the UK, Middle East, India, Australasia and Ireland, electricity is supplied at 230V or more. Electrical equipment worldwide is universal and works most efficiently at around 220V. Basic maths tell us there is an over supply here of 10-30V or more. This extra unused power dissipates as heat and vibration within machinery and equipment. Research suggests that an over supply in voltage of 10% (ie 220V to 242V) will reduce the life of electrical/electronic equipment by up to 90%, delivering another benefit from investing in VO.

Sounds too good to be true? It’s not, but there are pitfalls to avoid and the specification process should be executed in a robust and thorough manner in partnership with a proven supplier to ensure the correct system is specified.

Voltage optimisation

Voltage optimisation is an established and proven science dedicated to matching power demands to the needs of electrical equipment. It is straight forward, cost-effective and results-driven. Electricity bills can, theoretically, be reduced by as much as 25% but we find that our customers achieve between 15% and 22%. Systems are installed in series with mains electricity and ‘step down’ the power to the lower end of the voltage band (typically between 216V and 220V) but still within regulatory limits.


When investing in voltage optimisation it is imperative to understand exactly how each of the systems work and to research the market, questioning manufacturers and suppliers and requesting proof of fuel bill savings for individual projects. Get in touch with end users and ask about the installation and commissioning process and how much their electricity bills have fallen by in real terms. Also check other energy saving methods installed at the same time as the VO system, for example low energy light bulbs and movement sensors, and ensure savings figures are produced separately for each energy saving element.

Identifying the differences between VO systems is also hugely important given the major strides that have been made in improving the performance of this technology. Clients have the choice of two options – standard systems that utilise older technology, or new intelligent systems that are computer controlled to deliver improved performance.

Intelligent voltage optimisation

These systems, such as our Voltis solution, offer a number of benefits over traditional VO. Perhaps the two most important are zero risk to the electrical infrastructure and an in-built bypass function to switch them to standby should a significant mains voltage drop occur. For many of our customers this bypass function is probably the most significant feature of Voltis, which uses single phase auto-transformers to monitor voltage input and constantly adjusts voltage output to maximise savings and ensure supply integrity. It works on a supply reduction ratio of 1:0.92. Standard fixed ratio units work on a ratio of 1:0.945.

Having this fail safe automatic bypass means Voltis has a wider tolerance band on the voltage, allowing it to step down to 215V, for example, knowing that if mains voltage dips below that the system will go into automatic bypass rather than lower the voltage further. This not only gives customers a fail safe, it also delivers higher savings, typically double that of step down or fixed ratio optimisers.

Voltis also even out peaks, troughs and spikes as mains supply fluctuates, improves power correction factors, reduces harmonic distortion, balances the phases and automatically rotates auto-transformers to prevent overheating. Self-cooling (either by fan or air conditioning built in) can be specified. Voltis represents a significant step. As one of our customers said: “For us the best analogy is describing intelligent VO as a computerised fuel injection system and standard systems as carburettors. Technology has moved on and they represent the future.”


Further savings can be achieved if MTEM’s Sinergy sub-metering systems are deployed. Sinergy allows users to determine exactly where power is being used and then make properly informed decisions on how to reduce consumption. Typically, energy costs are one of the top three spends for most organisations, yet in many cases commercial and industrial entities are unable to determine exactly where this cost is incurred and how to reduce it. The first step has to be pinpointing exactly where and when energy is being consumed to enable users to identify potential waste. The Sinergy range offers non-invasive systems that are easy to install and can be fixed or portable, depending upon the individual application.

Standard voltage optimisation

Most standard voltage optimisation units use step down or fixed ratio transformers to reduce incoming voltage. The performance of these ‘dumb terminals’ varies and does not always deliver the desired results, either in savings or performance. Some can draw more power than the buildings they serve during moments of very low demand.

Generally, standard VOs achieve savings of 8% to 12% using a ‘one size fits all’ approach by reducing the incoming power level by a fixed ratio. These systems work adequately until there is a problem with the power supply, for example the mains supply dips. The unit will then keep dropping the voltage by whatever percentage it has been set at below mains, which can result in loss of power to the entire site.


Energy savings will vary from installation to installation, both for standard
voltage optimisation units and hi-tech intelligent systems. A free audit is the easiest way to discover what VO can do. Most standard units will achieve savings of approximately 8% – if manufacturers claim higher figures then take care to check them out. Install Voltis and you can usually double that saving. If the incoming voltage is especially high the savings will be greater.

Specification of an intelligent voltage optimisation unit will give customers a power supply that matches demand, cutting energy bills, safeguarding the power supply, lowering equipment maintenance and prolonging equipment life.

And it comes with the bonus of reduced carbon emissions and a major impact on corporate/social responsibilities.

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