29 April 2009
"If there was ever a time when we needed engineering excellence, I suggest this is it," said John Swaffield, president of Cibse in his opening address to this year's national conference in London.
That set the tone for the event as speakers got down to the nitty-gritty of telling it like it is in today's harsh economic climate: "sustainability" is no longer a buzz word or a goal. In fact, it is now "crap", noted by David Fisk, professor of engineering for sustainable development at Imperial College London.
That is not to say that smarter building services systems have had their day. Or that people clients should give up on lowering energy consumption. It means simply that those days of "green froth" are over. Bling has been bounced, said Fisk.
Clients want hard savings and the challenge of for building services engineers to make sure systems do what they say they will on package. Systems will be measured on their outcome not their potential. Clients will increasingly demand consumption be more carefully monitored.
Building services designer must rise to this challenge by insisting that commissioning periods are no longer an add-on to a contract that can be cut down in length or cut away completely to save money. These ship trials will become all important, said Fisk, and clients would do well to pay for a proper shakedown.
It's an issue that has dogged the building services designers and FMs, said one delegate over coffee. The public sector has been notorious in dumping commissioning and post occupancy evaluations. A good commissioning should last a year to ensure that all building management systems work as they should, which few do. This is partly because of architectural changes have been made with no updating of the BMS.
There was also a reality check for the retrofit market. Too many clients will "bolt-on, bolt-on, bolt-on" to existing equipment, said Julius Brinkworth, head of energy at Sainsbury's Supermarkets. There will come a time when you need to just rip it all out and start fresh. The reality is that clients will want tangible savings, that is: be large enough to measure, be able to be well monitored and be consistent. Payment to contractors will be based on these, he said.
Clients may complain about high energy consumption but a quick walk around a site will likely turn up lights blazing away at mid day, such as Terry Wyatt, consultant to services designers Hoare Lea found at Heathrow's new and extravagant terminal T5. The sad fact is you have to look hard to notice the lights are on because of the large amount of sunlight pouring into the building.
Designers, said Wyatt, must not try to be too creative in their systems in the name of energy saving. The more complicated, the more pitfalls. If a building has been designed and constructed to a BREEAM excellent rating, then if it fails to deliver on reduced consumption it should lose that rating, he said.
Similarly, wind power and ground source heat pumps have their limits of usefulness and installation issues of which clients need be aware.
Matthew Rhodes, managing director of Encraft, a supplier and manager of wind power equipment, from wind farms covering many hectares to micro-units atop single buildings.
A major truth about wind power is that little of the technology work well in urban settings. Buyer beware, said Rhodes. Too many customers come to them deciding they want wind power but base their decision on little more than a wet finger raised in the air. Also, a customer will buy a micro unit for their building based on the government's NOBAL estimates, which over-estimate of wind functions between 40 and 75 per cent of the time.
There can also be too much wind in the urban environment. In one client's case estimates were for average wind velocity in their area of up to 12 metres per second. In reality, given the open space atop the client's five-storey urban setting building, a 20 m/s speed was recorded which eventually trashed all five new turbines.
Ground source heat pumps are fashionable because of their ability to bring the water, between 11 and 13 degrees C, winter and summer, into a building. But their installation may require an open cheque book. Even with the best consultant geologists and hydrologists, you never know what you've got down there until you start drilling, said Paul Hancock, divisional technical director for NG Bailey.
Work on their Scottish headquarters was such a case he said. They had to keep drilling from first 20 metres to eventually 120 meters, and then even drill other holes to reach optimum volumes and pressures. Test holes need to be drilled, pressures measured and pumps tested.
Energy supplier firms will more often work with large community groups including cities and councils to study energy use patterns. This collaboration will be key to wiser consumption, said Mike Hogg, general manager of Shell gas direct that has around 10 per cent of the business market.
But, said Hogg, customers will have to get smarter at monitoring and managing their demand. For example, even now there is available automatic meter reading technology that operates through mobile phone technology. Data is uploaded to a server so the supplier can more accurately bill clients. But the data can also be shared with a client in any fashion they wish for them to better understand their energy consumption patterns.