November Refurb and Retrofit Magazine

Renewables & Sustainability
Hanover turn up the heat
When Hanover Housing Association decided to upgrade the heating at Ashfield Court, a complex of 22 flats, they hadn’t realised
at first just how different their ‘fuel switching’ would be.
Built in 1977, the flats were warmed by
electric night storage heaters which
had reached the end of their useful
life and need replacing.
Hanover Housing Association had this site
earmarked for ‘fuel switching,’ meaning that
they were intending to install a new mains
gas supply to the site with individual boilers
in each dwelling. However, the near-by gas
main did not have sufficient capacity to allow
the flats to be added to it. This meant
bringing in a new gas main from over 500
metres away. Additionally, due to the design
of the flats it was not easy to find suitable
locations for the flues - this ruled out gas as a
cost effective solution.
This ground source heat pump
upgrade project features:
• A Kensa Shoebox ground source
heat pump (6kW) in each flat
• New 150 litre unvented hot water
cylinders in each flat
• New radiators in each flat
• New heating controls in each flat,
which will be much easier for the
residents to use
• A ground source heat pump for the
site office
• 12 boreholes were drilled with
depths of up to 154 metres to form
a communal ‘micro district ground
source heat pump system’
Hanover decided to look at other options for
heating the flats and it became clear that a
micro-district ground source heat pump was
the best solution. Although the up-front
capital cost was more, the potential to
receive both ECO funding and RHI income
along with lower maintenance costs meant
that this system would more than pay for
itself in the long-run; it was the cheapest
long-term solution. In addition, the running
costs for the aged 55+ residents would be the
lowest possible, helping to address fuel
poverty.
All of this was enough to convince the
Hanover board to opt for Kensa micro-district
ground source heating. Designed for groups
of properties, Kensa’s micro ground source
heat network, also known as ‘district heating,’
provides each home with its own ground
source heat pump, ensuring heating and hot
water independence.
The ‘heat network’ is created by linking
multiple properties to a communal ground
array, designed to deliver an efficient, reliable
and durable source of heat for the life of the
property. And with no need for a plant room,
the micro district heat network solution also
overcomes the drawbacks of traditional
‘central plant’ district heating systems.
This project was the first using micro district
ground source heat pumps that Hanover has
been involved with, and they hope to use it
as a blueprint for future heating upgrades in
their housing stock, as they see the benefits
the system can bring to the tenants (lower
fuel bills) and to them as the landlord
(payback via the Renewable Heat Incentive).
www.kensaheatpumps.com
8 Refurb retrofit
magazine
Nov 2016 R2