No-one would ever dream of buying an exact copy of a piece of electronic equipment that they had bought 10/15 years previously as they would be only too aware that technological advances would mean that they could get a much improved version. But is the same true of other, perhaps even more fundamental energy using products that are to be found in every single commercial building in the UK?
We know pumps consume 10% of the world’s electrical power and have for decades been central to many aspects of commercial buildings. Despite playing a pivotal role in maintaining a buildings’ internal equilibrium and therefore its inhabitant’s wellbeing, with a replacement cycle of approximately 15 years, the decisions made, when the point of replacement is reached have important long-term energy ramifications.
As a pump manufacturer we are very aware that the entire replacement issue can be a ‘grey’ area that often slips under the energy use/best practice radar. Maybe because it is often service support staff who make the decision as to when a pump has reached the end of its useful life, perhaps due to the complexity of repair or the unavailability of particular spare parts. Then it is all too often a scenario where the details are simply read off the pump plate and an identical pump is reordered, or where if this has been discontinued, the closest alternative is sought.
The pump industry, like many engineered solutions driven businesses, is constantly evolving. It can be likened to the motor industry in many ways, especially when it comes to the dynamic pace of change that it has experienced in the past 20 years, especially with regard to developing more energy efficient solutions. However, even though there are similarities, most people change their car every 2/3 years so the pumps lifecycle at 15 years, makes it even more important that the right decision is made when the replacement cycle does come around.
When the pump or pump set was first specified, it would probably have been sized to meet an original duty or flow against a pressure, and to this was often an additional 10% leeway, purposely built in to cover ‘eventualities’, this over-sizing was (and in some instances still is) common practice. In fact we would estimate that 95% of the current installed pump base, in HVAC applications in particular, is incorrectly sized due to not only the addition of sizing in for an added comfort factor, but also because pumps are sized based on maximum demand, even though pumps will only need to work near the end of their curve for at most 5% of their lifespan.
So the first step should be to review the current system requirements as this will often lead to a more efficient pump selection that will offer the benefit of reduced energy consumption.
Once the correct duty has been ascertained, the next step is to check out the most energy efficient solution currently available to answer today’s need. Heating circulator pumps make up the majority of the replacement market within commercial services and today glandless circulators are the favoured choice because of their compact design and low maintenance. Glanded mechanical seal style products are however more efficient and can be fitted as a direct replacement for glandless circulators in some cases.
From 1 January 2013, a new EuP Directive comes into effect that will mean glandless standalone circulators, with the exception of those specifically designed for primary circuits of thermal solar systems and of heat pumps, will need to have an energy efficiency index (EEI) of not more than 0.27. With other ever stricter changes scheduled to take place in 2015 and 2020.
As it is the motor that is the energy sapping aspect of the pump, special focus should be given to this aspect and where conventional motors are used these should be as efficient as possible. In order to simplify the various current national standards that exist for motors, a new IE standard (International Efficiency class) has been adopted:
- IE1 = Standard efficiency (comparable to EFF2)
- IE2 = High efficiency (comparable to EFF1)
- IE3 = Premium efficiency.
Grundfos can offer a range of EuP ready products as well as super energy efficient Grundfos BLUEFLUX motors that meet the strictest demands that not only already meet the legislative demands that come into force in 2013 but also those that will come into force two year later in 2015.
Making the best pump decision really does add up - a 20% reduction in speed returns a 50% reduction in energy consumption and a 50% reduction translates into a huge 87% saving in electrical consumption - all based on cube law principles. In fact switching to high efficiency motors would save electrical power consumption which is equal to the total annual energy demands of 11 million people – the equivalent to the population of Greece.
Pump efficiency is improving due to many factors including improvements in pump design, the achievement of improved tolerances in manufacturing, better testing and when in the field, ease of service, accessibility of spare parts as well as a wide range of ancillary products that support the infrastructure they sit within.
Make sure advantage is taken of the latest technological advances by choosing to reselect every time a pump needs to be replaced. That way you will know you have achieved a win/win – by reducing energy usage and decreasing the buildings’ carbon footprint.