Annual Report and Accounts 2012/13 - Royal Devon & Exeter Hospital

56
2. Our Trust Royal Devon and Exeter NHS Foundation Trust
Annual Report and Accounts 2012/13
by approximately 350 tonnes per
annum. However, with investment of
approximately £1 million, it is capable
of running at a considerably higher
level of performance index of around
117%.
Action – Our Estates Department is
currently refurbishing the plant to
improve efficiency.
Second CHP at Wonford
(Carbon reduction target 500
tonnes per annum)
An additional CHP plant providing
1mW of electricity and potentially
1.4mW of heat would reduce carbon
emissions by approximately 500
tonnes. There would be potential
to add more CHP plant up to the
maximum electrical demand of
3.6mW, but the 5mW of resultant
heat produced would need a heat
sink (in the form of heating or steam
load) which is not currently available
at Wonford. Alternatively the heat
produced by CHP could be used to
drive an absorption chiller and
provide cooling.
Action – Pending the result of the
district heat scheme, a feasibility study
for a second CHP plant should be
commissioned.
Energy from waste installation
at Wonford (Carbon reduction
target 700 tonnes)
This scheme would involve the
installation of a new technology
pyrolysis heat treatment plant in the
waste management centre combined
with the conversion of the standby
steam boiler into a waste heat boiler
and the conversion of one of the
medium temperature hot water
boilers to steam as a backup for both
the existing CHP and the proposed
pyrolysis unit. All of the Trust’s clinical
waste could then be processed in the
pyrolysis unit and converted to heat
and vapour. The heat and vapour
would be used to provide energy to
the new waste heat boiler, provide
additional steam to the laundry and
Wonford site and potentially to a small
500Kw turbine producing electricity.
Pyrolysis is recognised as an Advanced
Conversion Technology (ACT) by the
Department of Energy and Climate
Change (DECC).
Action – To complete a technical
feasibility study on the Wonford site
and produce a Strategic Outline Case
(SOC) for the October 2014 Board
meeting. Estimated cost £1.2 million.
Photovoltaic (PV)
and Solar Thermal
Arrays (Carbon
reduction target 200
tonnes per annum)
The installation of 500Kw of PV
panels on the flat-roofed areas of the
Wonford site for micro-generation
of electricity directly into the hospital
mains supply. This would reduce the
maximum electricity demand as well
as provide low-cost electricity. The
installation would attract feed-in tariff
and it is anticipated that the payback
period would be approximately 10
years.
Action – To commission a site survey
at the Wonford site and produce
a feasibility study/SOC report by
September 2013. Estimated cost
£1 million.
Air and ground
source heat pumps
The use of ground source heat pumps
will be reviewed on a project by project
basis for each capital development.
Wind turbines
Due to planning restrictions and local
weather conditions it is unlikely wind
turbines will play a part in the Trust’s
energy strategy; however their potential
for use will be reviewed in all new
builds, on a project by project basis.
Biomass boilers
The remaining gas-fired boilers would
be partially replaced by biomass
boilers; these would provide the base
heating load for the main hospital,
with the variable element provided
by gas standby or other energy
sources, e.g. CHP or pyrolysis. Biomass
boilers require a resilient renewable
energy source, e.g. wood pellet. This
technology would therefore only be
possible if there is a sustainable supply
within the area. It would also attract
a Government Renewables Obligation
Certificate (ROC) income.
Action – Pending the result of the
District Heating feasibility study an
investigation into utilising biomass
boilers should be undertaken.