- 7 November 2007 -
Will sustainability end up costing the earth?
One way to cut down on energy use is to ensure that the pump is being worked as efficiently as possible and that means adjusting the speed of the pump to the actual need. Here, Linda Dingley looks at the approach by Grundfos with its E-pump technology.
The issue of sustainability is a foundation stone of today's environmental lobby. Yet there is nothing new about this, as all first and second world cultures still survive by using and reusing any materials that have an intrinsic value, from clothing to building materials. Sustainable development in buildings means different things to different people. However, the overriding principle is that to truly make a difference; every aspect needs to be considered from pre-design of the building through to its end-of-life deployment.
It is recognised that energy consumption in buildings accounts for nearly half of all the energy used in the UK . The government's white paper has set a target to reduce CO2 emissions by 60% by 2050. With 50% of this figure expected to come from improved energy efficiency. To achieve this, focus must be placed on:
. reducing primary heat losses through the façade
. reducing cooling loads
. introducing energy saving measures in the operation of the building
. installing energy creation support systems e.g. photovoltaics, geothermal.
The pump effect
Pumps are the single largest user of electricity in industrial and commercial applications in the UK consuming 47.24 TWh of electricity, which in turn represents some 32% of all electric motor consumption in industry and commerce.
The UK government's Department of the Environment, Food and Rural Affairs (DEFRA) have set specific targets for the savings they want to see from pumps:
. 1033 GWhr by 2010 (2%)
. 4265 GWhr by 2020 (9%).
So what impact can products and solutions have on achieving these targets?
E-Pumps
E-pump technology has been around for some years but the first product to integrate pump, motor, frequency converter and sensor into one unit was the Grundfos UPE Series 2000 circulator pumps that was launched fifteen years ago in 1992.
Many other products have since joined the variable speed portfolio and all applications that are suitable candidates for variable speed pump technology now benefit from having a wide range of options available to them.
Energy Labelling: In March 2005, four European pump manufacturers, who are in fact competitors, announced a high-profile agreement that would radically change the way that circulator pumps were sold. This agreement introduced what is currently a voluntary energy-labelling scheme to Europe.
The four companies who signed up to the scheme were: Grundfos Pumps (who initiated the scheme); Wilo; Smedegaard and Circulating Pumps who between them cover approximately 80% of the European market for circulator pumps.
Getting this scheme to launch was not a simple task, as huge variances in heating requirements exist between northern and southern Europe , as well as different levels of technological development between the East and the West. Therefore, major analysis had to be conducted to establish a common foundation. This process took four years to complete.
This result is based on the pumps EEI - Energy Efficiency Index - that is calculated according to an annual energy profile. The classification relates to independent circulator pumps with integrated pumps and motors. (see EEI chart)
Prime examples of 'A' grade pumps are the Grundfos MAGNAT and ALPHA ProT that mean energy savings of 75%+ for the end-user over fixed speed counterparts.
The technology behind these advances emanates from the development of permanent magnet motors, as these dramatically increase motor efficiency. They operate by drawing on the energy to drive the motor from magnets in the rotor, not just the mains. This allows these pumps to operate at optimal efficiency at any output. The integrated sensor monitors conditions in the system and a frequency converter then regulates the motor speed accordingly, so only the minimum power is used.
Put into place to support the Energy Labelling system the Energy Project show significant results right across Europe, with estimates that the amount of energy saved as a result of the installation of increased efficiency circulators in the 120 million private European residences, commercial buildings and light industry combined to make a saving of an astonishing 400 million kWh in the first year. This saving equates to the annual energy consumption of 88,000 homes.
Grundfos through varying lobbyist groups and industry bodies is trying to encourage the official adoption of this scheme to the full range of circulator pumps as well as to convert the current status of the scheme from voluntary to compulsory, initially within the EU.
Motoring on
A pumps electricity consumption accounts for about 85% of its total running costs. Therefore by ensuring that the pumps you select are fitted with ultra-efficient EFF1 motors, running costs will be kept to a minimum. Another benefit associated with pumps fitted with EFF1 motors is that the motor temperature runs lower than on a conventional motor. As the cooling fan is the main source of noise in electrical motors and because the high efficiency EFF1 motors need less cooling air, this allows for smaller cooling fans to be used, this in turn produces less noise. These motors are standard on the vast majority of Grundfos' pump range and the company is not charging its customers any premium for these energy saving products.
Sensors
The idea behind E-pumps is to adjust the speed of the pump to the actual need. Therefore, the pump needs to be informed about the actual condition of the system, by way of feedback.
For example, if we set the pump at a predetermined pressure, the sensor would feed the true status of the system back to the pump that would in turn vary the speed, to maintain this constant pressure.
Differential pressure sensors are the most common type for circulating pumps due to their reliability and cost-performance. Incorporation of differential pressure sensors in the pump system reduces the energy consumption considerably and increases pump performance.
Making sense
Advances in pump technology come in many guises. With electronics playing an increasingly important role, Grundfos have been looking to find answers that will offer significant benefits to the pump industry as well as further afield.
One such solution recently to hit the market is Grundfos Direct SensorsT an invention developed in the Grundfos labs that took more than 12 years of research and a 35 million Euro investment in material science to arrive at.
The solution provides a sensor with 2,500 layers of atoms that create an extremely robust nano-coating that is actually only 1 micron thick. The coating is able to withstand immersion in 100 C° hot water for more than 10 years and withstands contact with chemicals from pH 2 to 11.
Semiconductors
Grundfos manufacturers the MEMS (micro electro-mechanical systems) silicone pressure sensors at it's own state-of-the-art semiconductor fabrication facility under scrutinised conditions (Class 10 Clean Room) for achieving a highly corrosion resistant coating.
The coding on chip, print and finished sensor secures the chain of quality throughout the more than 400 semiconductor processes and offers traceability second to none in the industry. Furthermore, the pressure sensor is also manufactured and a nano-coating deposited on its surface in batches of 20,000 chips - every single chip being an exact clone of each other. This technique both prevents corrosion of the MEMS chip and enables direct media contact.
A look into the future
At the moment, the demand for E-pumps is exploding and with it, the demand for the revolutionary direct sensors. However, in the future the Grundfos Direct SensorsT will not just be able to control the differential pressure generated in the system. Combi-sensors will be able to measure more parameters in the water simultaneously. For instance, in hot-water circulating systems, a certain temperature is required at a water tap at the far end of the system. A sensor is placed in the far end of the system constantly informing the pump about the temperature status at this far end position. As a result, the pump is able to speed up, if the temperature goes down.
Next step
With the ever-increasing focus on energy efficiency and with sustainability being used as the new currency within building development, all should now be straightforward? The truth is however, that many of the key decision makers are still led by one factor and one factor only- profit.
When there is financial pressure on any project the red pen looks to see where cost savings can be made and one of the casualties of this is frequently the pump solution, especially when a variable speed option has been selected. At purchase, variable speed solutions are more expensive than fixed speed, however taking the Life Cycle Cost where 80%+ of the total cost is attributable to the energy needed to power it during its lifetime, this is a short sighted option, but one selected far too frequently.
Recent media focus has been highlighting the fact the government is not practising what it preaches in terms of energy conservation. If the same amount of attention were to be centred on this industry, the media would also find lots of positive talk and less real actual action.
To make a difference everyone needs to be step up to the mark - as the people who will judge whether we were successful in terms of creating sustainable solutions will be our grandchildren.
Contact
David Seamore
Grundfos Pumps Ltd
www.grundfos.com
Pump Industry Analyst
Sealing Technology
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