Step-down transformers do not save energy, whilst voltage optimisers definitely do
EMSc (UK) has acted swiftly to agree with the findings published by Salix Finance, in its recent report on step-down transformers.The Salix Finance report confirms EMSc (UK) Ltd’s own findings that step-down transformers do not save energy, but simply drop the voltage; a fact EMSc (UK) Ltd has been stating for over a decade. The report Salix released draws on a study carried out in Denmark, in which step-down transformers were used to identify energy savings on a variety of equipment, including motors. The results found the savings were insignificant, which only substantiated EMSc (UK) Ltd’s longstanding statement about step-down transformers.
However, confusing voltage optimisation transformers with step-down transformers could have huge implications for the voltage optimisation market, which depends on accurate information to highlight the technology’s true value as an energy saving solution.
For this reason, EMSc (UK) Ltd has clarified the difference between a step-down transformer and a voltage optimisation transformer.
What is a step-down transformer?
A step-down transformer changes the entire power output from one specific voltage to another. The transformer’s secondary winding that delivers the energy has less turns (coil) than the primary winding.
This type of transformer has many applications, such as enabling equipment from USA to operate in UK voltage conditions (i.e. 230V to 120V), and to transform 11,000V to 400V for HV distribution transformers in the UK. Although these devices reduce the voltage, they also increase the current and as a result, do not save energy.
What is a voltage optimisation (VO) transformer?
A VO transformer uses ‘negative voltage feedback’. It reduces only the voltage required, and then subtracts this voltage from the input voltage.
For example, to reduce the voltage from 240V to 220V, only the 20V are transformed and these are then subtracted from the input voltage by inducing a voltage in the opposite direction. This ensures that only around 1/10 of the power is transformed which results in a reduction of voltage, and current, thus significantly saving a large amount of energy.
Dr Alex Mardapittas, managing director of EMSc, commented on the Salix report, saying, ‘Recently, due to the popularity of voltage optimisation systems, a number of suppliers are importing step-down transformers, mainly from China, and selling them as voltage optimisation products. As a company manufacturing a true VO product – Powerstar – we are extremely happy to see the Salix report coming to light. The report proves the point we have been making for 13 years now, that using step-down transformers will not save energy.
‘We thank Salix for undertaking this exercise which we believe in the long term will protect the VO industry from inferior imported products such as step-down transformers. It is extremely important however, for companies to ensure what they purchase are true VO products and not the cheaper item on the market which, I can ensure you, are likely to be step-down transformers.’
The success of voltage optimisation technologies depends on the reliability, efficiency, and energy savings of the products sold and installed.