Energy Audit for St Mary Redcliffe Church, Bristol
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<strong>Energy</strong> <strong>Audit</strong> <strong>for</strong> <strong>St</strong><br />
<strong>Mary</strong> <strong>Redcliffe</strong> <strong>Church</strong>,<br />
<strong>Bristol</strong><br />
“Sustainability is about achieving the correct balance between social,<br />
economic and environmental issues, a successful programme will<br />
deliver value over time, it will not be a cost burden. There is not one<br />
solution to achieve success but a toolbox of solutions from which<br />
experience is needed to select the right solutions <strong>for</strong> each project.”<br />
Matt Ful<strong>for</strong>d 06 January 2014 Version 1.0
1. Introduction<br />
This report has been prepared to detail the energy saving measures and renewable energy<br />
generation potential that exist at <strong>St</strong> <strong>Mary</strong> <strong>Redcliffe</strong> <strong>Church</strong>, <strong>Bristol</strong>.<br />
Given that <strong>Bristol</strong> will shortly be the Green Capital of Europe and <strong>St</strong> <strong>Mary</strong>’s <strong>Redcliffe</strong> is a prominent<br />
and highly visible civic building within the city the church is keen to demonstrate its commitment to<br />
long term ‘green’ and sustainable issues.<br />
The report was prepared following a site audit conducted by Matt Ful<strong>for</strong>d, Inspired Efficiency on 11 th<br />
November 2013.<br />
A summary of recommendations is made in Section 7 of this report.<br />
In general summary the energy reduction strategy <strong>for</strong> the church should be to install good controls<br />
to the heating and low energy (LED) lighting alongside considering installing a PV system to the<br />
roofs. Such a strategy, when fully implemented could reduce the current energy consumption by<br />
30-40%.<br />
The findings of this report in no way negate the PCC of <strong>St</strong> <strong>Mary</strong> <strong>Redcliffe</strong> to petition <strong>for</strong> a faculty in<br />
order to conduct any works at the church. For further advice on the requirement <strong>for</strong> a faculty the<br />
church should seek advice from the DAC Secretary.<br />
"One of the core Christian beliefs is that God created the world and that world<br />
was teaming with life of all kinds. This life is seen as precious to God, and part<br />
of the task of humanity is to keep that world, and all its creation safe. We face<br />
a major environmental crisis at the present time, and it seems that this has<br />
been caused by humanity not being careful enough with God's wonderful<br />
creation. As part of the churches mission, we need to do all we can to make<br />
this wonderful creation a part of our concern and that means we need to take<br />
seriously all that can ensure we use our resources well. This energy audit is<br />
part of that process."<br />
2
2. <strong>Church</strong> Details<br />
<strong>St</strong> <strong>Mary</strong> <strong>Redcliffe</strong> is a very large church within the Diocese of <strong>Bristol</strong>. It is located in central <strong>Bristol</strong><br />
and dates back to the 12 th century. It is reported to be the highest building in <strong>Bristol</strong> and has fine<br />
gothic architecture, as such it attracts a high number of visitors and is open daily with daily prayer<br />
and worship.<br />
2.1. Listed <strong>St</strong>atus<br />
<strong>St</strong> <strong>Mary</strong> <strong>Redcliffe</strong> is of a Grade I listed status. This listing has been taken in to account when<br />
determining the recommendations <strong>for</strong> energy saving measures and renewable energy within this<br />
building.<br />
2.2. Size<br />
From plans of the church provided the church area of the church has been measured as 1,500m 2 .<br />
From discussions on site with members of the church during the audit it has been established that<br />
the typical usage of the church is <strong>for</strong> 277 hours per month.<br />
Description<br />
Average Monthly<br />
Use<br />
<strong>Church</strong> Use<br />
4 Sunday Services, open from 8am to 8pm (mid-week 52 hours/month<br />
and other services held in weekday opening times<br />
below)<br />
Community Use Open <strong>for</strong> visitors 8.30am to 5pm Monday to Saturday 221 hours/month<br />
Administration None (separate parish office) -<br />
Catering and Events Concerts 4 hours/month<br />
TOTAL<br />
277 hours/month<br />
3
2.3. Current <strong>Energy</strong> Usage<br />
Annual energy bills <strong>for</strong> the church have been provided and examined. With the exception of the<br />
kitchen gas, bills provided have covered the 6-7 months from April 2013 and have been extrapolated<br />
to provide estimates of annual usage.<br />
There are four area of metered energy use:<br />
<strong>Church</strong> Electricity – currently provided by Southern Electric providing a 100kVa 3 phase<br />
incoming supply located in the base of the porch.<br />
Café Electricity – currently provided by Southern Electric providing a quarterly supply <strong>for</strong> the<br />
café usage in the undercroft.<br />
Heating Gas – serving the main boilers <strong>for</strong> heating and hot water <strong>for</strong> both the church and the<br />
café<br />
Kitchen Gas – serving the cookers and the like <strong>for</strong> the café.<br />
These show that the current carbon footprint of the church is 113.18tCO2e per year.<br />
Carbon Footprint (tonnes/year)<br />
1%<br />
61%<br />
26%<br />
12%<br />
<strong>Church</strong> Elec<br />
Café Elec<br />
Heating Gas<br />
Kitchen Gas<br />
kWh/year Cost/kWh Total £ Total CO 2e<br />
Electricity (<strong>Church</strong>) 57,337 10.303p £5,907.43 29.84<br />
Electricity (Café) 25,456 10.303p £2,622.73 13.25<br />
Gas (Heating) 372,599 2.7853p £10,378.00 69.01<br />
Gas (Kitchen) 5,856 2.7853p £163.11 1.08<br />
TOTAL 461,248 £19,071.27 113.18<br />
The annual energy consumption has been taken from the energy bills provided from April 2013 to<br />
September 2013 and extrapolated to estimate annual useage. These may include the use of<br />
estimated readings where actual readings have not been taken.<br />
Note: The above costs are <strong>for</strong> the energy only and do not include standing charges, VAT etc<br />
4
In comparison with national benchmarks <strong>St</strong> <strong>Mary</strong> <strong>Redcliffe</strong> consumes 68% more heating fuel than<br />
would be expected <strong>for</strong> a church of this size and 91% more electricity. However these benchmarks<br />
are based on the ‘average’ church and as <strong>St</strong> <strong>Mary</strong>s <strong>Redcliffe</strong> has much loner opening times than<br />
most churches it should be expected to be over these benchmarks. However a focus on good energy<br />
management <strong>for</strong> bringing the consumption down to typical benchmark levels is there<strong>for</strong>e advisable<br />
prior to installing renewable generation. Recommendations on how to reduce gas and electricity<br />
consumption at the church are covered in this report and are estimated to bring the church within<br />
the typical benchmark range.<br />
kWh/m2<br />
<strong>St</strong> <strong>Mary</strong> <strong>Redcliffe</strong><br />
kWh/m2<br />
benchmark (typical)<br />
kWh/m2<br />
benchmark (good)<br />
Electricity 38.2 20 10<br />
Heating (gas) 252.3 150 80<br />
The church currently has energy tariffs <strong>for</strong> both gas and electricity which have been well procured<br />
and are at the lower end of the normal range of market prices.<br />
All energy bills should apply the VAT rate of 5% due to the charitable status of PCC’s and this is being<br />
correctly applied at this church.<br />
5
3. Electrical Saving Recommendations<br />
3.1. Internal Lighting<br />
The energy used <strong>for</strong> the internal lighting within churches and similar buildings typically makes up the<br />
largest use of electricity (except where all electric heating is installed) and there<strong>for</strong>e savings made to<br />
this area can result in significant overall reductions to energy usage.<br />
The internal lighting within the <strong>Church</strong> has been surveyed by Mike Ludlow of Specialist Lighting<br />
Services (see separate report) and it is recommended that the following improvements are made.<br />
3.1.1. Replace bulbs/lamps within existing fittings<br />
The following lights can simply have a new low energy bulb fitted to them to generate an energy<br />
saving.<br />
Location Existing Lamp Type Recommended Lamp<br />
Type<br />
Choir Vestry 6ft T8 Fluorescent tubes Philips Master<br />
LEDtube<br />
Cleaners GLS Bulkhead<br />
LED retrofit lamp<br />
Cupboard<br />
Shop Display<br />
Cabinets<br />
30W fluorescent tubes<br />
(6nr)<br />
LED tape strip<br />
North<br />
Entrance<br />
Door<br />
Café Kitchen<br />
35W MR16 Halogen<br />
uplighters and 58W T8 5ft<br />
fluorescent tubes<br />
58W T8 5ft fluorescent<br />
tubes (3nr) and 36W T8<br />
LED MR12 and<br />
Philips Master LED<br />
tube<br />
Philips Master LED<br />
tube<br />
4ft fluorescent tube (1nr)<br />
Choir <strong>St</strong>alls R80 downlights Replace <strong>for</strong><br />
Megaman CFL R80<br />
downlight<br />
MR12 as per trial<br />
http://www.tlcdirect.co.uk/Products/MGR8015ES.<br />
html<br />
Choir <strong>St</strong>alls 15W Pygmy lamps 2W LED Pygmy lamp http://www.simplelighting.co.uk/p<br />
roducts/Megaman-2W-Pygmy-<br />
Dimming-Warm-White-LED.html<br />
Ambulatory 35W MR16 uplights LED MR12 lamps As per trail<br />
North and<br />
South<br />
Transepts<br />
North and<br />
South<br />
Transepts<br />
Organ<br />
Nave<br />
Nave<br />
Gardeners<br />
<strong>St</strong>ore<br />
35W MR16 uplights<br />
(24nr)<br />
28W SDC candle lights<br />
(20nr)<br />
28W SDC candle lights<br />
(5nr)<br />
28W SDC candle lights<br />
(60nr)<br />
35W MR16 uplights<br />
(40nr)<br />
GLS Bulkhead<br />
LED MR12 lamps<br />
LED candle lights<br />
LED candle lights<br />
LED candle lights<br />
LED MR12 lamps<br />
LED replacement<br />
As per trail<br />
http://www.heritagelighting.org/pr<br />
oducts.php#myTab<br />
http://www.heritagelighting.org/pr<br />
oducts.php#myTab<br />
http://www.heritagelighting.org/pr<br />
oducts.php#myTab<br />
As per trail<br />
6
3.1.2. Replace existing lighting with new lower energy fittings<br />
The following lights should be replaced with new fittings generate an energy saving.<br />
Location Existing Lamp Type Recommended Lamp Type<br />
Central Crossing 400W mercury<br />
LED flood light<br />
discharge lights<br />
Café<br />
150W HQI Uplights<br />
(2onr)<br />
Wall lights as per SLS<br />
report<br />
Lady Chapel Halogen AR111<br />
projectors and Metal<br />
LED spot and flood<br />
lighting as per SLS report<br />
Halide HQI flood lights<br />
Nave, Chancel 250W HQI Metal Halide LED flood lights as per the<br />
and Transept<br />
Ambulatory<br />
Crossing/Chancel<br />
<strong>St</strong>ep<br />
Nave<br />
External Lady<br />
Chapel Roof<br />
uplights (36nr)<br />
150W HQI Metal Halide<br />
downlights (6nr). 100W<br />
Halogen AR111<br />
projectors<br />
100W Halogen AR111<br />
projectors<br />
150W HQI Metal Halide<br />
uplights (12nr)<br />
300W Halogen<br />
Floodlighting<br />
SLS report<br />
LED lighting scheme as per<br />
the SLS report<br />
LED flood lights as per the<br />
SLS report<br />
LED flood lights as per the<br />
SLS report<br />
LED floodlighting<br />
It is also noted that the lighting report recommends a new lighting scheme to the <strong>St</strong> Johns Chapel<br />
Full running costs and wattages have not been detailed within the SLS report so detailed costs and<br />
savings cannot be calculated however it can reasonably be estimated that by upgrading all the above<br />
lighting (both bulb changes and fitting changes) savings of around 50% will be achieved saving the<br />
church around £3,000 per year on electrical costs. In addition the proposed new lights (both bulbs<br />
and fittings) are much longer life and would there<strong>for</strong>e also provide a maintenance saving from<br />
reduce lamp replacements.<br />
7
3.2. Mains Supply<br />
The <strong>Church</strong> has an incoming three phase mains electrical supply<br />
and a supply voltage of 237v. (Note the second meter appears to<br />
be <strong>for</strong> the phone mast). This voltage is higher than required and<br />
could explain some of the reason <strong>for</strong> the higher incidents of<br />
lighting replacement. The voltage can be reduced to around<br />
220V quite safely and without affecting the per<strong>for</strong>mance of any<br />
of the electrical equipment. Reducing the voltage will not only<br />
produce an energy saving but will also help to protect any<br />
lighting and sound equipment from problems associated with<br />
high voltage which can shorten their life. A simple 100A 3 phase<br />
unit can be obtained from SavaWatt controls (Campbell Hodgetts<br />
– 07767 306463)<br />
3.3. Small Power<br />
During the site visit it was noted that there are other small electrical usages, the most significant of<br />
which is likely to be the organ blower however this does have inverter drives on the motors and<br />
there<strong>for</strong>e no further recommendations are made in this regard.<br />
8
4. Heating System Saving Recommendations<br />
4.1. Boilers<br />
The heating within the church and also to the café is served from boilers located in a basement<br />
boiler room to the north side of the church.<br />
Within this boiler room there are two Ideal Concord CXS 100kW gas boilers. The boilers are thought<br />
to have been installed around 2000 and are currently in reasonable condition and while more<br />
efficient models are now available there is no immediate benefit to be obtained from replacing<br />
these boilers at this time.<br />
At the end of life of these boilers the consideration can be made to more efficient heating solutions<br />
however the fluing arrangement from the boiler room does not allow <strong>for</strong> condensing boiler to be<br />
installed and it would be difficult to justify a biomass boiler against the efficiency use of a mains gas<br />
supply.<br />
4.2. Pipework and Distribution<br />
The pipework within the boiler rooms is steel and some copper. Some<br />
of the main pipework is well lagged but other lengths are exposed.<br />
Additional lagging to un-lagged pipework, valves and other fittings<br />
should be undertaken to ensure the maximum amount of heat output<br />
from the boiler goes into the church. Sustain (a <strong>Bristol</strong> based company)<br />
should be contacted to arrange <strong>for</strong> a free survey and quotation.<br />
http://solutions.sustain.co.uk/Valve%20and%20Pipework%20Insulation<br />
The main heating pump within the church is aged and would benefit<br />
from replacement with a new dual pump set which has variable speed<br />
drives integrated to the pumps. By having two pumps (a duty and<br />
standby) there will be additional resilience in the event that one pump<br />
fails.<br />
9
4.3. Radiators and other heat emitters<br />
The heating within the church is supplied via underfloor heating pipes to cast iron column radiators.<br />
It is reported that the heating is satisfactory in heating the church.<br />
The floor trenches around the church in which the heating pipes run do serve as a source of heat<br />
emission. The heat put of these can be substantially improved firstly by lifting the grilles and cleaning<br />
out the built up dust and debris within these trenches and then lining the base and sides of the<br />
trench with a flexible thermal foil insulation to promote the heat to be emitted up and out the top of<br />
the trench through the grille rather than warming the ground beneath. Such insulation rolls are<br />
available easily from mainstream DIY stores (http://www.wickes.co.uk/invt/210022) and can work<br />
very effectively.<br />
The heating system has indications that a Fernox inhibitor has been installed and the water within<br />
the radiators was checked and found to be clean. It is recommended that the levels of inhibitor<br />
within the system is check annual and part of the boiler service and topped up as required.<br />
10
4.4. Controls and Frost Protection<br />
The heating controls to the church are whole inadequate. They currently consist of a time clock<br />
which is not in use and a range of on and off switches. The electric immersion heater to the hot<br />
water tank is currently switched on so that both gas and more expensive electricity is being used to<br />
heat the hot water.<br />
There is also a three port valve controlled by an actuator which switches the output of the boiler<br />
between the heating and/or hot water. This actuator switch is broken and needs to be replaced to<br />
allow <strong>for</strong> effective control<br />
As there is no operating time clock the heating is currently turned on manually in Mid-October and<br />
turned off in March. During the winter the heating there<strong>for</strong>e runs constantly 24 hours a day, 7 days a<br />
week. There is some thermostatic control with the use of a Drayton SCR Digistat located in the north<br />
side of the choir stalls but it is not clear how this is connected back to modulate the boiler firing.<br />
It is strongly recommended that the control panel is replaced with a modern control unit such as a<br />
DC1100 controller which includes weather optimisation and has time clocks <strong>for</strong> heating and<br />
separately <strong>for</strong> hot water. This has an optimiser so will automatically bring on the heating to bring the<br />
building up to temperature by the time set within the programmer. There is also frost protection<br />
settings on external air temperatures, internal space temperatures and the temperature of the<br />
water in the heating pipes so that minimum levels of heating can be maintained <strong>for</strong> purposes such as<br />
the organ.<br />
The hot water is currently running constantly as well as having the electric immersion turned on. As<br />
the primary use of hot water is <strong>for</strong> the café and WC’s it is recommended that the hot water is<br />
provided <strong>for</strong> the times when the café is open. Outside of these time the hot water tank will continue<br />
to store hot water until it is used up there<strong>for</strong>e there will still be hot water available in the toilets<br />
after the 3pm café closing time. In order to maintain levels of hot water on a Sunday and Monday is<br />
it recommend that the hot water comes on <strong>for</strong> two hours in the morning to heat up the tank.<br />
All recommended timings are shown in the table below<br />
11
HEATING<br />
Monday -<br />
Saturday<br />
Current Recommended Notes<br />
On Off On<br />
(Optimised)<br />
Off<br />
(Optimised)<br />
Running Constantly 8am 5pm<br />
Sunday Running Constantly 6.30am 8pm<br />
HOT WATER<br />
Tuesday -<br />
Friday<br />
Running Constantly 7am 3pm<br />
Saturday Running Constantly 8am 3pm<br />
Sunday and Running Constantly 8am 10am<br />
Monday<br />
The current set point <strong>for</strong> the church is 18 deg C which is appropriate <strong>for</strong> the type of use.<br />
Other settings should be made as follow:<br />
Optimiser - Combined<br />
Optimised <strong>St</strong>op – Enabled<br />
Day Economy – Enabled<br />
Outside Frost – 1 deg C<br />
Space Frost – 10 deg C<br />
Boiler Return Frost – 4 deg C<br />
Boiler Set Point – 75 deg C<br />
The establishment of proper control to the heating system is estimated to save the church in the<br />
region of £2,500 per year in gas consumption.<br />
12
5. Building Fabric<br />
While it is acknowledged that the potential to undertake significant improvements to the traditional<br />
fabric are limited there are a number of areas noted below where improvements can be made which<br />
will result in a reduced amount of energy and improved levels of com<strong>for</strong>t being achieved.<br />
5.1. Roof<br />
There is a roof space between the stone vaulted ceiling of the church and the metal roof covering<br />
above. This is accessible from the tower of the stairs. This roof space is currently un-insulated. The<br />
thermal mass of the stone vault will provide a degree of thermal per<strong>for</strong>mance but this could be<br />
improved by adding insulation within this roof space. This could be installed by an insulation<br />
contractor such as Aran Service (https://www.aranservices.co.uk/pages/336/Loft-Insulation/).<br />
Insulating the roof will slightly increase the surface temperature of the stone ceiling which will<br />
improve the perceived thermal com<strong>for</strong>t of those people within the church. This is not a priority but<br />
could be considered alongside other works in the area.<br />
5.2. Walls<br />
Given the historic nature of the building and that the walls are exposed both internally and<br />
externally no improvement recommendations have been made in this regard.<br />
13
5.3. Floors<br />
The floors within the church are mainly solid within<br />
the aisles and transepts. To the pewed area of the<br />
nave there are raised timber floors which are likely to<br />
have a void beneath. This area could be insulated to<br />
reduce heat loss through the floor and raise the<br />
surface temperature of the floor to improve com<strong>for</strong>t<br />
however there are historic pews fixed on top of this<br />
floor and there<strong>for</strong>e access is difficult. This<br />
recommendation should only be considered if the<br />
pews are being removed <strong>for</strong> other (reordering) works.<br />
5.4. Windows<br />
The pointing and glass within the windows was briefly checked and found to be in good condition.<br />
There is little improvement that can be carried out to this area with drastically and detrimentally<br />
affecting the appearance and there<strong>for</strong>e other than ensuring that the pointing to the abutments<br />
remains in good condition there are no recommendations to be made in this area.<br />
5.5. Doors<br />
There are two main doors to the church (North and South).<br />
The North door is the main door to the church that is used by<br />
visitors and is left open <strong>for</strong> much of the time.<br />
In order to reduce cold draughts it is recommended that<br />
draught strips are neatly rebated into the sides of the south<br />
door, especially at the base, to provide a better sealing when<br />
the door is shut.<br />
To the north door it is recommended that an overhead door<br />
air curtain is provided. This should be connected to the main<br />
heating system (spurred off from the nearby radiator) with a<br />
fan that will blow warm air down over the open door and<br />
prevent the large amount of heat loss from this door when<br />
open. Such a unit would need to be fixed within a well design<br />
boxing in order not to affect the visual appearance of the<br />
church.<br />
14
6. Renewable <strong>Energy</strong> Feasibility<br />
6.1. Solar Photovoltaics<br />
The main roof of the church (above the main nave and chancel) faces south. This roof is a large area<br />
and hidden from view by the stone parapet to all sides. Non-visible solar PV array are acceptable on<br />
grade one listed buildings and precedent exist with arrays on <strong>St</strong> James, Piccadilly, London and more<br />
locally at <strong>St</strong> Michael’s and All Angels, Withington both of which are grade 1 listed CofE churches. The<br />
roof has a shallow pitch of around 15 degrees and has a lead covering with lead rolls.<br />
The roof structure appears very solid and capable of taking the additional weight of a self-weighted<br />
system. The cables from any PV array could be run down the tower into the electrical incomer room<br />
at the base where there are spare ways within the existing distribution boards making the electrical<br />
connection very straight<strong>for</strong>ward.<br />
The main consideration <strong>for</strong> any solar PV array will be<br />
the fixing of the panels onto the existing roof and any<br />
fixings which penetrate the existing lead must be<br />
avoided. A self-weighted system should there<strong>for</strong>e be<br />
proposed and it is likely that a bespoke framing and<br />
weighting system will have to be used. This was<br />
achieved at <strong>St</strong> Michael’s, Withington (pictured) albeit<br />
with more of a pitch. With careful consideration such<br />
a non-fixed self-weighted system could be designed<br />
<strong>for</strong> this church. Installation contractor has been<br />
consulted with <strong>for</strong> advice on this installation and it<br />
may be possible to use an adapted <strong>for</strong>m of the<br />
Schletter Alugrid ballasted system to achieve this.<br />
15
The pinnacles along the parapet could cause some shading issues and there<strong>for</strong>e it is recommended<br />
that any potential array is installed with a solar edge or micro panel mounted inverter which will<br />
reduce any losses if panels are partially shaded. In the calculations below and allowance of 25%<br />
shading has been made in light of this issue.<br />
Having run the various calculations given the area and dimensions of the roof it appears that the<br />
best layout and size of array is to consider two rows of 30 panels giving 60 panels in total. This would<br />
provide a 15kWp system.<br />
Such a system has been estimated to cost in the region of £22,000. (This excludes VAT that the<br />
church may be able to recover).<br />
The system, once shading, orientation and pitch, have been considered, is estimated to generate<br />
9,968kWh per year. As such it would provide 17% of the churches current electrical consumption<br />
although with a low energy lighting scheme this could increase to providing around one third of the<br />
electrical needs of the church.<br />
The PV system would benefit from 20 years income from the governments Feed in Tariff scheme and<br />
if installed in the near future would ‘buy-in’ to this scheme at a rate of 12.57p/kWh <strong>for</strong> every kWh<br />
generated. In addition the church would gain from any electricity exported at the rate of an<br />
additional 4.64p/kWh. For most of the time the church will, rather than exporting the electricity, use<br />
the electricity on site and there<strong>for</strong>e avoid purchasing electricity at the current rate of 10.03p/kWh.<br />
For the purposes of calculations it is assumed that a site uses 50% of the energy it generates and<br />
exports 50% of the energy however it is likely that the church will use a greater percentage of the<br />
energy generated and there<strong>for</strong>e the savings figures are slightly conservative.<br />
Given all the above the system would generate savings and income totalling in the region of £2,000<br />
per year. This would there<strong>for</strong>e deliver a simple payback of 11 years. Once energy price inflation is<br />
factored in the payback is estimated to be 9.5 years and provide an annual return on investment<br />
(RoI) of 7.9%.<br />
The installation would require a mobile crane to lift the panels and ballast onto the roof and <strong>for</strong> edge<br />
protection to be temporarily added to the parapets <strong>for</strong> safe working on the roof. The works would<br />
then be carried out with the contractor gaining access up the tower stairs.<br />
For further details on a potential PV system contact Solar Solutions Malvern Ltd, 01684 893000<br />
David McCann (Managing Director), 07824 832274, david@solarmalvern.com .<br />
Funding in <strong>for</strong>ms of grants, <strong>for</strong> the installation of renewables mostly stopped with the Feed in Tariff<br />
introduction a few years ago and it is not possible to use money from public sources (which includes<br />
Lottery Grants) to fund renewable installations and gain from the Feed in Tariff (or renewable heat<br />
incentive) as this would be against the European <strong>St</strong>ate Aid rules. The use of more local ‘trust’ based<br />
funds can be possible as can the use of some of the Landfill Tax Credit schemes although care needs<br />
to be taken on how these are structured as some allow such schemes and other do not.<br />
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6.2. Micro-Wind<br />
Micro wind units require highly exposed sites and should be located 250m way from buildings. The<br />
grounds surrounding the church are there<strong>for</strong>e not suitable wind generation.<br />
6.3. Micro-Hydro<br />
Hydro electricity is a highly efficient source of renewable energy but requires a flowing body of<br />
water with a differential height, this is not present at this site and there<strong>for</strong>e such an installation<br />
would not be feasible.<br />
6.4. Solar Thermal<br />
Solar thermal installations are best suited to heat water <strong>for</strong> use in washing up, hand washing and<br />
bathing. There is a demand <strong>for</strong> this with in the café and WC’s but this is minimal and located a<br />
reasonable distance from the south facing roofs with good solar potential there<strong>for</strong>e it is not<br />
recommended within the current arrangement however the use of solar thermal should be<br />
considered as part of any new development on the site which involved hot water.<br />
6.5. Ground Source Heat Pump<br />
Such a system also produces a low grade heat (around 45deg C) whereas the current heating system<br />
to the church requires a high grade heat (around 80 deg C) and there<strong>for</strong>e would require very<br />
substantial alterations to enable it to work with heat pump based systems. The use of ground source<br />
would there<strong>for</strong>e not be advised with the current arrangement.<br />
Parts of the site are of a high historic nature and as such the archaeological implication of drilling<br />
bore holes would also preclude a viable installation, the area to the North of the church is less so<br />
and could provide a location <strong>for</strong> bore holes should such a solution be the best option.<br />
Heat pump solutions work best with underfloor heating systems and in turn underfloor heating<br />
system are most economical in buildings which are in constant use (nursing homes, prisons,<br />
hospitals etc.). For new development on the site the use of a heat pump could be considered if the<br />
building is likely to have a usage which was extensive however the extensive ground works would<br />
still pose significant challenges.<br />
The use of heat pumps still require electricity to power the pumps and given that there is mains gas<br />
present on the site a heat pump would need to have a coefficient of per<strong>for</strong>mance (CoP) of at least<br />
2.75 (i.e. <strong>for</strong> one unit of electricity one obtains 2.75 units of heat) during winter conditions as this is<br />
the relative difference in moving from mains gas to electricity in both carbon and cost terms. The<br />
high efficient use of mains gas can often prove the most cost and environmentally efficient solution.<br />
6.6. Air Source Heat Pump<br />
An air source heat pump system runs from electrical power but in a very efficient way however there<br />
are no carbon or cost benefits from running an air source heat pump when compared with an<br />
efficient gas boiler due to the CoP of air source heat pumps. It has similar issues as the ground<br />
source heat pump and we would not recommend that an air source heat pump is considered.<br />
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6.7. Biomass<br />
The use of biomass as a fuel <strong>for</strong> the church boilers instead of mains gas could be considered. The<br />
main issues are the delivery and storage of the biomass pellets. Given the location of the church<br />
along a main road and the proximity of the boiler room to this road access there are no issues with<br />
delivery of the fuel. There is some space in the basement area around the boilers which could be<br />
adapted <strong>for</strong> storage but in order to store sufficient volumes the possibility of building a biomass fuel<br />
store above the boiler room may need to be considered and whether a low height construction here<br />
(say 1.5m tall) would be acceptable. Given the level differences in the area it is considered that it<br />
may be viable to design and well consider store above the existing boiler room.<br />
There is a fine balance as to the environmental and cost benefits of using biomass in lieu of mains<br />
gas. In off gas grid situations where the fuel source is fuel oil biomass provide clear benefits but<br />
biomass burns less efficiently than gas and gives of greater levels of other flue gas pollutants such as<br />
NOx.<br />
Enquires should be made of John Coffey (Managing Director), PV World Ltd Mobile: 07701 028339,<br />
Telephone: 01580 764401, Email: john@pvworldltd.co.uk who can review the current arrangement<br />
and offer suitable proposals.<br />
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7. Summary of Recommendations<br />
This report has made numerous recommendations on improvements that can be carried out to<br />
reduce energy and carbon emissions from the operation and use of this building.<br />
These have been summarised here into three phases taking into consideration the payback, capital<br />
investment and ease of carrying out each improvement. There is also logic in the phases of<br />
improving the current arrangement so that decisions on more major elements can be based on<br />
improved efficiencies rather than less than optimal situations. These recommendations and this<br />
report should be presented and an action plan developed to implement as many of these actions as<br />
possible.<br />
In general the energy strategy <strong>for</strong> the church should be to install good controls to the heating and<br />
low energy (LED) lighting alongside considering installing a PV system to the roofs.<br />
The use of other renewable heat sources should be careful considered as to whether they are truly<br />
more environmentally efficient than the very efficient use of mains gas.<br />
Immediate / Short Term<br />
Improvement Measures<br />
Description Estimated Cost Estimated Saving To be actioned by<br />
Install full controls to the £4,500 £2,500 per year<br />
heating and hot water<br />
system<br />
Replace lamps within<br />
existing lighting fittings<br />
<strong>for</strong> low energy versions<br />
SLS to advise SLS to advise<br />
Arrange <strong>for</strong> the<br />
uninsulated pipework<br />
fittings in the boiler<br />
room to be insulated<br />
Replace the main heating<br />
pump with a VSD pump<br />
set<br />
Clean out the heating<br />
pipe within floor<br />
trenches and line with<br />
insulating foil.<br />
Consider the installation<br />
of a 15kWp solar PV<br />
array on the south facing<br />
roofs of the<br />
nave/chancel<br />
£600 £200/year and<br />
improved resilience of<br />
heating system<br />
£1,500 £400/year<br />
£1,500 £350/year and<br />
improved com<strong>for</strong>t<br />
£22,000 £2,000/year<br />
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Medium Term<br />
Improvement<br />
Measures<br />
Description Estimated Cost Estimated Saving To be actioned by<br />
Install new LED SLS to advise<br />
SLS to advise<br />
lighting to replace<br />
existing fittings<br />
Install 3phase 100A £3,100 £480/year<br />
Voltage optimisation<br />
on mains electrical<br />
incomer<br />
Add an air curtain<br />
over the north door<br />
heated from the<br />
LPHW heating system.<br />
£3,000 Improved com<strong>for</strong>t<br />
Long Term<br />
Improvement<br />
Measures (with<br />
reordering)<br />
Description Estimated Cost Estimated Saving To be actioned by<br />
Add insulation to roof<br />
Improved com<strong>for</strong>t<br />
void<br />
Add insulation to void<br />
Improved com<strong>for</strong>t<br />
beneath pew<br />
plat<strong>for</strong>ms<br />
Replace boilers at end<br />
of life with high<br />
efficiency models and<br />
consider biomass.<br />
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