ABB Drives achieves 90% energy savings for Coutts & Co
A massive
saving in energy usage is being achieved by an international banking
company on its air conditioning system following the installation of ACS
600 drives from ABB.
- 90% savings in energy
- £70,000 reduction in annual energy bill
- Hot water used effectively
- Drives co-ordinated with BMS
| Equipment: |
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One 9kW, one 22kW and two 75kW drives |
| Savings P.A.: |
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£70,000 |
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To reduce its
energy costs, Coutts & Co specified drive technology from ABB for
its air conditioning plant. |
Energy Problem
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ABB Inverter Solution
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| Coutts and Co is the international private banking arm of the
Natwest Group in London. The bank recognised that the cost of
energy would be a significant factor in its continuing operations.
It wanted to reduce the operational costs of its air conditioning
system. It also wanted to coordinate control of the indoor
climate with an integrated Building Management System.
Under the previous regime, all of the pumps in the air
conditioning system were operating at 100% power continuously.
Maintenance costs were high and downtime had a marked effect on the
efficiency of the plant. |
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Variable speed drives were recommended for fitting
to the pumps throughout the air conditioning system. Areas
where pumps were identified that would benefit from the use of
variable speed drives included the chilled, hot and condenser water
systems. The medium pressure water system for the boiler room
was also identified as giving suitable savings. Four drives were
fitted to the system. These included a 4kW and a 22kW drives
as well as two 75kW variable speed drives. Sensors were fitted
in the pipe work connected to the drives to help regulate the speed
of the pumps and ensure optimum use of the water's energy content. |
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ABB Inverter Benefits
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| The cost benefits were immediate with Coutts and Co able to save
some £70,000 per annum. In addition, there were other benefits
from reduced maintenance. Using variable speed drives meant
that the speed of the pumps could be reduced to about 40 per cent of
maximum speed leading to a marked drop in energy usage. The
lower pump speed also reduces wear, saving on maintenance costs.
The hot water is also used more effectively resulting in a saving in
gas costs. The return water is no 8oC
lower than the outgoing water.
Confirms Mike Ingram, Facilities Manager at Coutts & Co: "The
pumps are running at about 40% of maximum speed whereas before they
would be running at 100% continuously. In addition, the hot
water is used more efficiently, saving gas. Before we would
pump water out at 40oC. Now the return water is at 32oC."
The systems is integrated with the Building Management System
enabling easy control of the indoor climate. |
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| Notes Mike Carman, Business Development Manager for HVAC at ABB:
"This installation shows the staggering energy savings that can be
achieved with variable speed drives. This is because the
variable speed drive runs the motor at the speed needed by the
process, rather than running the motor continuously at full speed
irrespective of the requirements". |
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Banks and other
similar buildings can benefit from energy savings in their HVAC
plant. |
| Simple recirculation is the least efficient way of
running a pump as the pump runs at full speed regardless of the
output needed. Small decreases in pump speed regulated by a variable
speed drive can give large energy savings. |
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