Sustainable Design within BSF: A Case
Study of the City of Leicester College
Liam Murray (Hulley & Kirkwood)
City of Leicester College – Leicester BSF
•The current scheme comprises of a complete new build of a predominantly two storey school.
•The school is to accommodate 1500 pupils and is a business specialist college.
•Has received carbon 60 funding of £50/m2 to achieve a carbon reduction of 60% over 2002 levels
Design Philosophy
Education
• Engaged in workshops with students and staff
• Engaged in workshops with De Montfort University
• Visual displays of energy consumption
• Use the energy data for teaching resource
Building Fabric
Massively Improved Fabric:
• Glazing U-value improvement 2.2 to 1.5 W/m2
• Wall U-value improvement 0.35 to 0.15 W/m2
• Roof U-value improvement 0.25 to 0.1 W/m2
• Floor U-value improvement 0.25 to 0.1 W/m2
• Air permeability of 3 m3/hr/m2 @ 50Pa
Building Fabric Impact
Building built to Part L 2006 & 2010 minimum standards peak boiler requirement 1450kW
City of Leicester with improved fabric peak boiler requirement 680kW
53% reduction in boiler size!!!
Solar control
• Dynamic thermal simulation to optimise solar control and building form
• Glazing g-values of 0.36 in area’s of high solar gain
• Internal blinds fitted
• Strategic placement of brise-soliel and roof over hangs
Energy Reduction
• Good daylighting
• Lighting controls – Daylight linking and PIR’s
• Low watt computers – 80w each (50% less than an average PC)
• Low flush WCs
• Mixed Mode - Natural ventilation with boost ventilation during peak summer and peak winter
• Variable speed pumping with remote differential pressure monitoring to reduce pump duty by up to 51%.
Good lighting design impact
• Better working environment for students
• Reduction in FM call outs
• Added security
• 63% reduction in annual lighting energy
Heat recovery & Efficient space conditioning
• All AHU’s to incorporate high efficiency heat recovery some units achieving +70%
• Evaporative cooling within large AHU’s to allow lost cost cooling to air systems
• Future heat input of renewable technologies ASHP, GSHP, Solar thermal catered for within AHU
LZCT Feasibility Study
WIND
+ FITS Benifits
- Site Suitability
GSHP
+ Heating & Cooling
- High capital cost
BIOMASS
+ High carbon savings
- Negative payback
SOLAR PV
+ FITS Benefits
- High £/CO2 install
CHP (BIO-CHP)
+ Produce Heat & Elec
- Maintenance required
SOLAR THERMAL
+ High CSR
- Peak’s in summer
Weighted CO2 savings
-
1,000,000
2,000,000
3,000,000
4,000,000
5,000,000
6,000,000
7,000,000
8,000,000
9,000,000
10,000,000
CH
P
Bio-C
HP
Solar therm
al
GS
HP
- vert
GS
HP
- horiz
AS
HP
Biom
ass
Wei
gh
ted
CO
2 sa
vin
g
Typical School
25, 60 & 100 yr life cycle Saving
-£500,000
£-
£500,000
£1,000,000
£1,500,000
£2,000,000
£2,500,000
£3,000,000
CH
P
Bio-C
HP
Solar therm
al
GS
HP
- vert
GS
HP
- horiz
AS
HP
Biom
ass
60
yr L
CA
25 yr LCA NPV
60 yr LCA NPV
100 yr LCA NPV
15 Yr Net present value
-£500,000
-£400,000
-£300,000
-£200,000
-£100,000
£-
£100,000
£200,000
£300,000
CH
P
Bio
-CH
P
Sola
r therm
al
GS
HP
- vert
GS
HP
- horiz
AS
HP
Bio
massN
PV
(£)
Typical School
Selected LZCT – PPO-CHP
• Pure Plant Oil CHP powered by locally sourced fuel
• Sized to meet the base domestic hot water load
• High efficiency back-up gas fired boilers
• Carbon 60 funding
• Double Renewable obligation certificates - ROC’s
• Excellent £/CO2 (£800 per tonnes)
• Short Payback (6-8 years)
• Energy on demand
LZCT future expansion
Allow for future developments in the renewable market now
Up rated roof structure to take PV
Additional coils in DHW cylinders
Spare tails on LTHW headers
AHU which allow LZCT inputs
May be feasible in a few days/month/years
Packaged M&E Plant
• Allows quick installation which when timetabled can dramatically reduce project impact on students education
• Reduces noise during installation
• Allows most efficient design without restraints of building form and structure
• More cost effective way of providing m² for plant space
• Allow quick and low impact servicing/ replacement of plant
Design estimates
51% reduction in CO2 emission’s over 2006 standards (Stage C energy model)
76% reduction in CO2 emission’s over 2002 standards (carbon calculator)