Best Practice Actions in the University of St Andrews

5th February 2013

Dr John Smith, Building Manager, North Haugh

Water Recirculating System• Proposed centralised water recirculating cooling unit for lab equipment

• What we have implemented

GasesExisting

New Piped Gases

Fume Heat Reclaim Run around coils on fume extracts – tried first in UK at MSB

View glass to check condition of zinc coated copper coils

Fume Heat Reclaim

MSB =7 Run around coils on fume extracts BSRC = same but coils coatedto common header and preheat coil on with Blygoldmain teaching classroom AHU

Energy Costs

Electricity Gas

Purdie Building £474k £109k

BMS Building £188k £109k

Fume Cupboards

No of F/C’s With Sash Closures Potential Old Style

BMS Annexe 16 16

BMS 54 0 54*

Purdie 130 37 58 33

* Out to tender

Fume Cupboards Premier – glass linedOnly one bank 24hrsoperation

General - separate AHU for each lab to minimise air flow

Upgrading Fume Cupboards

Automatic sash closer with presence detection

•Schneider closer fitted by Premier Labs - developed for St Andrews

•Sash user controlled by push button

•Presence detection lowers sash if user is away from cupboard for more than 10 minutes

•Retrofitted to existing fume cupboards

Automatic Fume Cupboard Sash Closer

Automatic Fume Cupboard Sash CloserBEFORE•Sash manual operation by users•Observation shows sashes left open at night and over 500mm minimising containment.

AFTER•Sashes always closed at night, and for long periods during the day•User acceptance crucial – selling the energy message•Powers up in 2 stages to 200mm & 500mm. Users find 200mm adequate•Trialled at prestigious lab for best roll out•Salix funded £9,468 for 9 sashes•Saving 19.5 tCO2/yr•Saving over 50% supply air •Saving in running cost £3,268•2.9 yr technical payback

Automatic Fume Cupboard Sash Closer

Comments

•Energy calculations based on reduction of supply make-up air

•Electricity at 8.8p/kW, heat at 3.25p/kWh averaged over payback period

•Evaluation process under way from actual data from lab supply air handling unit – temps / air flow rate / fan power / heating coil energy

Fume Cupboard CalculationsSash Down Sash at 200mm Sash at 500mm

Individual Sash info a 1200 mm 1200 mm 1200 mmb 50 mm 200 mm 500 mmc 0.06 m2 0.24 m2 0.6 m2d 0.3 m/s 0.3 m/s 0.3 m/s

AHUMeasured at AHU e1 565 l/s 831 l/s 1696 l/s

e 0.5650 m3/s 0.8310 m3/s 1.6960 m3/sf 2034 m3/h 2991.6 m3/h 6105.6 m3/hp 1.205 kg/m3 1.205 kg/m3 1.205 kg/m3

mass flow 0.6808 kg/s 1.001355 kg/s 2.04368 kg/soa 8 oC 8 oC 8 oC

Supply temp ob 21 oC 21 oC 21 oCdt 13 oC 13 oC 13 oC

cpa 1.0035 kJ/kgK 1.0035 kJ/kgK 1.0035 kJ/kgK

Energy to heat the air q/hr 8.9 kW 13.1 kW 26.7 kWyear 77,004 kWh 113,258 kWh 231,149 kWh

Measured at AHU AHU Motor 0.10 kW 0.40 kW 0.75 kWelect 867 kWh 3,468 kWh 6,503 kWh

total 77,871 kWh 116,726 kWh 237,653 kWhActual measured diversity 1 1 1

year 77,871 kWh 116,726 kWh 237,652 kWhrate 15 tCO2 23 tCO2 46 tCO2

0.0325 £/kWh inc losses gas cost £2,503 £3,681 £7,5120.089 £/kWh elec cost £77 £309 £579

total cost £2,580 £3,990 £8,091

Observed Current Situation hrs/day 2 4 18Total energy 204,182 kWhTotal Carbon 40 tCO2

Total Cost £6,948 yr

With Autosash Closers hrs/day 16 4 4Total energy 110,977 kWhTotal Carbon 21 tCO2

Total Cost £3,733 yr 54%

SAVING Total energy 93,205 kWh  Total Carbon 18 tCO2  Total Saving £3,215 yr

North Haugh Building Complex

CHP Engine – BMS Annexe

Energy Costs

Electricity Gas Electricity to Purdie Gas to Purdie

Purdie Building £474k £109k

BMS Building £188k £109k

BMS Annexe (BSRC) £79k £51k

CHP £3.7k £138k £59k £39k

Helium Recovery

Environmental Driven Energy Saving

Resource Dwindling ‘Run Out In About 15 Years’

Helium Recovery

Helium Recovery

Helium Recovery UnitLiquid helium used to cool EPR samples, liquid supplied from BOC at a cost of £864 per 120 litres (weekly)

Gas collected in a balloon, pressurised into cylinders. Cylinders transported to a helium cryogenic plant in Physics. Liquid used in Physics

Cost of unit £28,380. Electrical installation cost £2,500. Total = £30,880

Recovery 50% saving of £432 per dewar

Payback of 1.5 years

Note: Due to problem with world supply, delivery cut to fortnightly