We are being constantly bombarded with environmental messages via every medium. With the Kyoto Protocol finally in force, seven years after it was first ratified, there is at last a sense of urgency and a belief that maybe, just maybe we can do something to turn the tide.

Great technological strides have been made in terms of continuing to develop more and more energy efficient products, for an audience who are becoming increasingly aware of the potentially lethal environmental time bomb we have unwittingly created.

The construction industry has not always been noted for its eagerness to embrace change, there is something of a ‘if it isn’t broken don’t fix it’ attitude. So, as an industry, the construction area has sometimes tended to lag behind ‘newer’ areas and has been slower to embrace new developments. This has been one of the hurdles to overcome in order to encourage consultants and contractors to consider new developments within the pump and pumping solutions markets.

Variable speed/e-pumps

Variable speed pump technology is not new – the technology has been integrated into circulator pumps that have been available to the market since 1992. It was Grundfos who led the market by integrating pump, motor, frequency converter and sensor all into one unit.

Since then, more and more e-pumps have been made available to the market, with increasingly sophisticated electronics and higher efficiency motors. In some instances these pumps can save an incredible 76 percent, over their fixed speed counterparts.

There has been extensive media coverage within industry specific magazines over the intervening years about the undoubted benefits of using variable speed technology. Not only because these pumps will only use as much energy as they require to perform the given task, but also because prior to their introduction pumps tended to be over-sized (to allow for an extended safety margin), this factor also contributed to their greater ‘thirst’ for energy. The UK has generally been slower than their European counterparts in terms of embracing variable speed technology – recent internal research has shown that in 2004 – 17 percent of all relevant sales were e-pumps (this had increased from 10 percent in 2002). This is however way behind countries like Germany, The Netherlands and Belgium, and also Poland and Hungary who would traditionally not be considered to have strong environmental credentials.

Integrated solutions

New builds within the commercial building sector are becoming increasingly sophisticated and a much more integrated approach is being taken at all stages of new developments.

The new Welsh National Assembly Building is due to be fully completed by August 2005 and is an excellent case in point. The initial brief looked in detail at all aspects with regard to sustainable development including:

• design life of 100 years • use of indigenous materials • minimise energy consumption and waste • to be an ‘exemplary’ building in terms of sustainability

The building is 5,000 square metres, and the roof and frame are constructed from timber and steel with the outer walls mainly being constructed from slate and glass (1,000 tonnes of Welsh slate have been used on the project). The total cost of the project is expected to be £40.9m.

Environmental modelling studies indicate that the building has an energy consumption currently running at approximately half the current best practice for office buildings (75 kW hours per square metre compared to 130 kW hours per square metre).

As part of the drive to reduce the building’s overall energy consumption, natural ventilation has been incorporated as the primary source of ventilation to virtually all areas of the building. There are also a number of unusual environmental features incorporated into the building. For example the Debating Chamber, Committee Rooms and associated public viewing galleries will be served by a mixed-mode ventilation system that offers both natural ventilation and air conditioning. The system incorporates a ‘roof cowl’ that rotates with changes in wind direction to produce a negative pressure on the leeward side of the cowl, allowing hot air to be drawn out of the debating chamber to the outside atmosphere.

The ground is used as a heat source/sink in the form of earth heat exchangers, coupled with heat pumps to reduce the size of conventional boilers and dispense with the need for chillers. The ground source heat pump system will also provide low-grade heat that can be used for the underfloor heating system.

To minimise carbon-dioxide emissions, wood (biomass), being essentially environmentally friendly, will be used as a combustible fuel source. An additional gas fired boiler will be installed, but will only be used in emergency situations.

Another interesting aspect of the overall project are the water saving measures. Rainwater collected from the roof via the steel columns supporting the roof will supply the toilets and provide the water for window washing.

With such a strong emphasis on ‘green’ principles, it is not surprising that the range of in-line centrifugal pumps at the heart of the operations are all electronically speed controlled.

Another building that has captured the hearts and minds and attracted enormous amounts of media attention is 30 St Mary’s Axe. This building is London’s first environmental skyscraper and is better known as the Swiss Re building. Its instantly recognisable shape has lead to a number of nicknames being attached to the building – however the aerodynamic design maximises the amount of natural lighting and ventilation that significantly reduces the buildings energy consumption.

A comprehensive range of sustainable measures mean the building will use 50 percent less energy than a traditional prestige office building.

A distinct jewel in the Foster Studio crown is this 180m 40-storey tower sheathed in steel and glass. It breaks with the conventions of traditional box-shaped office buildings through its circular design - it is tapered at the base and the crown to improve connections to the surrounding streets and allow the maximum amount of sunlight to the plaza level which contains a lively mix of shops, cafes and restaurants.

The real environmental achievements however are in the internal design. Fresh air is drawn up through the spiralling light-wells to naturally ventilate the office interiors and minimise reliance on artificial cooling and heating. The lightwells and the shape of the building maximise natural daylight.

As you would expect from such a ‘ground-breaker’ – electronically controlled pumps have been used throughout – including on the fourpump booster set. With a 180m building, ensuring sufficient water is available, especially given that the restaurant/bar areas are at the top of the building, is crucial. This is a radical building – socially, environmentally, spatially and architecturally.

The Future

The pump industry has gone through something of a quiet revolution in recent years, with the development of improved efficiencies due to the arrival of e-pumps and more efficient motors. One of the consistent messages the industry has been sending out in recent years, is around the subject of Life Cycle Costs – which clearly shows the purchase and maintenance costs associated with a pump are only a small fraction of its lifetime cost.

Pumps and pumping systems can often have an expected life  span of 20 years – this means we need to take action now. Anyone who specifies pumps needs to be conscious of their actions and the real responsibilities they carry in assisting in the attainment of the Kyoto Protocol targets. Until other ‘alternative’ energy sources are developed, we will continue to be heavily reliant on gas and electricity to provide the power needed to keep the country working. Pumps are at the heart of all these systems and will continue to play a significant role; many pump manufacturers will continue to invest heavily in developing increasingly efficient pumps that place as little strain on the environment as is possible.

The amount of focus on developing ‘total’ building solutions will continue to grow. The days of isolating different facets of a buildings design and focussing on them in a disingenuous way is over.

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