Aecom Report On Life Cycle Costing:
Continuous Flow Up To 7% More
Cost Effective
AECOM, a major global player in the building engineering services consultancy arena, has concluded a report
showing that continuous flow water heating systems have a clear advantage in terms of initial capital costs as well
as life cycle costs over 20 years, when compared with stored hot water systems*.
The study** shows that continuous flow
water heating systems can be up to
7% more economical than equivalent
‘traditional’ stored hot water systems.
AECOM was commissioned to carry
out a life cycle study on continuous
flow water heating systems, and to
provide a comparison with conventional
storage systems. Two case studies were
provided that are based on projects using
continuous flow water heating systems.
AECOM then determined an equivalent
storage based system for each case study
and compared operational and capital
costs.
For the life cycle comparison, the analysis
period was 20 years, based on the
expected service life. The net present
value (NPV) calculation is based on a
discount rate of 3.5% (The GREEN BOOK
- HM Treasury), an inflation rate of 2% for
servicing costs and projected retail fuel
costs from DECC1.
In both case studies the continuous flow
system showed a clear advantage in terms
of initial capital costs, as well as life cycle
costs over 20 years, with the continuous
flow system consistently lower in energy
use than the two storage systems.