IMPROVING COLD STORAGE AT KING’S COLLEGE

IMPROVING COLD STORAGE AT KING’S COLLEGE

Allison HunterSchool of Biomedical Sciences

Waterloo Campus and Guy’s Campus

Guy’s Campus (and the Shard)

New Hunt’s House

How much energy are we using? £80,257Takes timeConsistent way of recording informationType of energy monitor – ease of useStaff – audit number and types of freezers Cold storage units:New Hunt’s House (NHH) 500 Franklin-Wilkins Building (FWB) 300

-80°C freezers

Equipment Make Model kWh/ day

Freezer -80°C NBS U535 13.3

NBS U535 14.4

Heraeus Herafreeze 21.2

Heraeus Herafreeze 19.6

Nuare Glacier 19.3

NBS U570 Premium 11.5

Freezer -70°C Haier DW-86L388 12.0

-20°C Freezers

Equipment Make Model Temp/Capacity

kWh/ day

Freezer -20°C Liebherr No frost -20°C/400litre 1.17

Freezer-20°C Liebherr Premium -20°C/400litre 1.23

Freezer-20°C Liebherr Premium -20°C/200litre 1.15

Freezer-20°C Electrolux - -20°C/200litre 1.60

Fridge Freezer Liebherr Comfort +4°C /-20°C 0.59

Housekeeping measures

Once per month -De-ice with a scraper-Clean the foam grill in front

of the compressorAsk staff to minimise door openingDefrost every six months to a year in back up freezersOffer dry ice service to sort freezer stocksOne unit in; one unit outAdvise leavers to discard or redistribute stocksRack or SLS FRE2130 £30 for 12 box FRE2228 Grid DividerEquipment alarm system – freezers running too cold

T-scan equipment alarm

How can we reduce the energy we use?

Savawatthttp://www.savawatt.co.uk/images/db/dt_casestudies/9/casestudy.pdf

NHHCurrent total cold storage energy spend £80,257485 units were fitted costing £32,692 or £67.41 per unitThis saves 67.87 tonnes CO2 and £15,783.08 per year (20%).

(icemakers; 4°C incl cold rooms; 4°/-20°C & -20°C only)

Savawatt Control

Funding for Savawatt devices

Salix

http://salixfinance.co.uk/

Revolving Fund with a minimum and maximum spend each year

Loan Scheme which can be used to fund other projects

What else can we do?

Change freezer temperatures

-80°C freezers vary between 14-21 kWh/day -70°C reading is 12kWh per day

Present data on energy consumption to staff (talk then email)Cascade to divisional staff and studentsVoluntary reduction not compulsoryTech staff liaise between groups to alter settings on shared freezers

Individual freezer costs

-80°Ccost per annumU570HEF £306 NBS -80°C (one model) £562 Revco £850 -70°C

Haier DW-86L388 £438

Outcome of freezer temperature requestFreezersThe total number of freezers reduced from -80°C to -70°C is: 19 (FWB 12 and NHH 7) about 30% of our collection. We have a total of 63 low temperature (all originally -80°C) freezers in two buildings: New Hunt’s House (NHH) has 38 and Franklin-Wilkins Building (FWB) has 25.

Freezer numbers

FWB 12 out of 25NHH 7 out of 38

-70°C/-80°C freezer costs in NHH & FWB

Freezer type kWh/day Number of days

Cost of electricity(£)

Cost per annum (£)

Number of freezers

Cost per annum(£)

minus 80°C 17.6 x 365 x .1 642.40 x63 40471.20

minus 80°C 17.6 x 365 x .1 642.40 x 44 28265.60

minus 70°C 12 x 365 x.1 438.00 x19 8322.00

36587.60

saving £3,883.60

minus 70°C 12 x 365 x.1 438.00 x63 27,594

saving £12,877.20

0.00

2,000.00

4,000.00

6,000.00

8,000.00

10,000.00

12,000.00

14,000.00

-80°C Freezer -70°C Freezer

Cost comparison of running 19 units in £ per year

Tonnes of CO2 produced by 19 units

0

10

20

30

40

50

60

-80°C freezer -70°C freezer

How to work out CO2 usage and savings

minus 80 minus 70

6424 4380 kWh

x0.48357 x0.48357 defra factor

3106.45kgCO2 2118.04 kgCO2 sub total

x 44 x19 freezers

136683.95 kgCO2 40242.70 kgCO2 total

x19

59022.55 kgCO2 Minus 40242.70 kgCO2 18779.85 kgCO2

59.02 tonnes CO2 40.24 tonnes 18.78 tonnes

C02

http://www.theccc.org.uk/tackling-climate-change/reducing-carbon-emissions/what-can-be-done/

Search defra carbon conversion factors 2013http://www.ukconversionfactorscarbonsmart.co.uk/

For the above I used the Defra carbon conversion factor of 0.48357 kgCO2/kWh. For cost, I would normally use 10 p/kWh as that’s the current total cost including all charges.

Summary of cost and CO2 savingsNHH £ Tonnes C02

Total previous cold storage spend

80257

Savawatt controls savings -15783 67.86

subtotal 64471

-80°C to -70°C savings on 7 units

1430

Current cold spend 63044

£80257 minus £63044 = 17,213

FWB

-80°C to -70°C savings on 12 units =

2453

18.78

Total savings in NHH & FWB £19,666 86.64

Can you reduce your freezer requirements?Flinders Universityhttp://www.nfstc.org/pdi/Subject03/pdi_s03_m04_02_d.htm

Supplierhttp://www.whatman.com/NucleicAcidandProteinSamplePreparation.aspx

Franklin-Wilkins Building

Collaboration

Technical managers

Technicians

Academics and researchers

Procurement and

Purchasing

Estates and Energy

Environmental waste

Hodgkin Building

Roll out to other buildings

The proposed batch of 147 Savawatt controls for:Hodgkin Building, Henriette Raphael, Shepherd’s House and Britannia House are expected to save 23 tonnes CO2 and £4,751.41 per year. Current cost=£24,092.48

Other estate includes Wolfson Wing, Hospital Trust embedded space at Guy’s and St. Thomas’, Denmark Hill Campus

Conclusion

Audit Identify the quantity of high ticket itemsRecord Consistent recording

units kWh/day; calculate CO2

Building electricity metersReduce consumption Talk to staff, email follow up

Savawatt saves 20% energy

Freezers at -70°C saves 20-30% energy

Alternative storageFunding Salix; EstatesTotal lifespan costs Energy usage and waste disposal costs

Thanks

Technical staff: Resource Managers:Carlos Roncancio-Garcia Jo Cunningham Pranetha Baskaran John Darker

Stuart Fleming Steve Franey

Kelvin Howell Will Heal

Estates: Rosie CalokatsiaKeith McIntyre Dave StantonLisa Ward Sarah Meredith Kat ThorneRichard DaviesTristam Slater Colin Chinnery (Purchasing)

Allison HunterDeputy School Resource ManagerKing’s College LondonTel 020 7848 6163Email allison.s.hunter@kcl.ac.uk

SavaControls: How they work

Power In Solid State Switch

The solid state switch switches for a longer or shorter time, depending on the load on the motor, 100 times a second

SavaControl

Compressor

SavaControls: What are they

Electronic controllers which reduce the electricity used by electric motors when

operating under part load conditions.

They do this in two ways, by:1. Improving the motor efficiency2. Modulating the power input according to

the motor loading.

Savawatt calculationsRefrigeration is never switched of and compressor run times will vary depending on type of equipment, what it is used for, how often the door is opened, how old it is etc. We take an average compressor run time as sixteen hours per day of which 80% of the time the motor will be in a part load condition. (part load is when the SavaControl reduce consumption) The formulae for annual electrical consumption is: amps x volts x hours run x power factor =kWhrs per annum 1000 With numbers of a simple -20 freezer = 1.3amps x 240 volts x 4672 (80% of 16x365) x 0.8 (compressor motor power factor) = 1166kWhrs per year 1000 SavaControls will save 20% per annum on single phase applications. On the above the saving will be 233kWhrs, based on an electricity cost of 10p/kWhr a saving of £23.32 per annum will be achieved. The basic SC3 @ £34.00 (plus installation) offers a payback around 1.5 years.

SavaControls: How they workThe effects of SavaControls on the Voltage and Current Waveforms

Energy Consumption 100% Energy Consumption 80%

Approximately 20% Savings!

No SavaControl With SavaControl

-80°C to -70°C cost savings calculations

-80°C freezer at 17.6 kWh per day x 365 x .10p kWh =£642.40 x 44 freezers = £28,265.60 per annum and 136.68 tonnes CO2-70°C freezer at 12.0kWh per day x 365 x .10p kWh = £438.00 x 19 freezers = £8,322.00 per annum and 40.24 tonnes CO2 Total cost saving per annum by reducing temperatures on 19 freezers has been £3,883.60 (Cost of 19 freezers at -80°C at 17.6 kWh per day x 365 x .10p kWh =£642.40 x 19 = £12,205.6)Total CO2 reduction 18.78 tonnes (19 -80°C freezers 59.02 tonnes CO2 compared to 19 -70°C freezers 40.24 tonnes CO2)

NHH -80°C to -70°C cost savings for 7 units

Freezer type kWh/day Number of days

Cost of electricity(£)

Cost per annum (£)

Number of freezers

Cost per annum(£)

minus 80°C 17.6 x 365 x .1 642.40 x 7 4496.80

minus 70°C 12 x 365 x.1 438.00 x7 3066.00

saving £1430.80

FWB -80°C to -70°C cost savings for 12 units

Freezer type kWh/day Number of days

Cost of electricity(£)

Cost per annum (£)

Number of freezers

Cost per annum(£)

minus 80°C 17.6 x 365 x .1 642.40 x 12 7708.80

minus 70°C 12 x 365 x.1 438.00 x12 5256.00

saving £2452.80

Drying cabinets

FWB 5.118 one cabinet measured at 14.3 kWh/dayTimers on at 7am and off at 7pm would save: 14.3 x 0.5 x 3 cabinets x 365 days= 7829 kWh p.a. (x.10p kWh = £780 per annum in one lab alone) and 3.78 tonnes CO2.

FWB 5.48 one drying cabinet uses 42.78 kWh/day 1.78 kWh X .10pkWh = 18p or £1.78 for 24 hrs or x365 days = £649.70By using a 12 hour timer we would save £323.96 per annum and 4.04 tonnes CO2.