How much energy are we using? £80,257 Takes time Consistent way of recording information Type of energy monitor – ease of use Staff – audit number and types of freezers Cold storage units: New Hunt’s House (NHH) 500 Franklin-Wilkins Building (FWB) 300
Housekeeping measures Once per month -De-ice with a scraper -Clean the foam grill in front of the compressor Ask staff to minimise door opening Defrost every six months to a year in back up freezers Offer dry ice service to sort freezer stocks One unit in; one unit out Advise leavers to discard or redistribute stocks Rack or SLS FRE2130 £30 for 12 box FRE2228 Grid Divider Equipment alarm system – freezers running too cold
How can we reduce the energy we use? Savawatt http://www.savawatt.co.uk/images/db/dt_casestudies/9/casestudy.pdf NHH Current total cold storage energy spend £80,257 485 units were fitted costing £32,692 or £67.41 per unit This saves 67.87 tonnes CO 2 and £15,783.08 per year (20%). (icemakers; 4°C incl cold rooms; 4°/-20°C & -20°C only)
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 students Voluntary reduction not compulsory Tech staff liaise between groups to alter settings on shared freezers
Individual freezer costs -80°Ccost per annum U570HEF £306 NBS -80°C (one model) £562 Revco £850 -70°C Haier DW-86L388£438
Outcome of freezer temperature request Freezers The 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.
-70°C/-80°C freezer costs in NHH & FWB Freezer typekWh/day Number of days Cost of electricity(£) Cost per annum (£) Number of freezers Cost per annum(£) minus 80°C17.6x 365x.1642.40x6340471.20 minus 80°C17.6x 365x.1642.40x 4428265.60 minus 70°C12x 365x.1438.00x198322.00 36587.60 saving£3,883.60 minus 70°C12x 365x.1438.00x6327,594 saving£12,877.20
Cost comparison of running 19 units in £ per year
How to work out CO 2 usage and savings minus 80minus 70 64244380kWh x0.48357 defra factor 3106.45kgCO 2 2118.04 kgCO 2 sub total x 44x19freezers 136683.95 kgCO 2 40242.70 kgCO 2 total x19 59022.55 kgCO 2 Minus40242.70 kgCO 2 18779.85 kgCO2 59.02 tonnes CO 2 40.24 tonnes18.78 tonnes
C0 2 http://www.theccc.org.uk/tackling-climate-change/reducing- carbon-emissions/what-can-be-done/ Search defra carbon conversion factors 2013 http://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 CO 2 savings NHH £Tonnes C0 2 Total previous cold storage spend 80257 Savawatt controls savings-1578367.86 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£19,66686.64
Can you reduce your freezer requirements? Flinders University http://www.nfstc.org/pdi/Subject03/pdi_s03_m04_02_d.htm Supplier http://www.whatman.com/NucleicAcidandProteinSamplePreparat ion.aspx
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 CO 2 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 items RecordConsistent recording units kWh/day; calculate CO 2 Building electricity meters Reduce consumption Talk to staff, email follow up Savawatt saves 20% energy Freezers at -70°C saves 20-30% energy Alternative storage FundingSalix; Estates Total lifespan costs Energy usage and waste disposal costs
Thanks Technical staff: Resource Managers: Carlos Roncancio-GarciaJo Cunningham Pranetha BaskaranJohn Darker Stuart FlemingSteve Franey Kelvin HowellWill Heal Estates:Rosie Calokatsia Keith McIntyreDave Stanton Lisa WardSarah Meredith Kat ThorneRichard Davies Tristam SlaterColin Chinnery (Purchasing)
Allison Hunter Deputy School Resource Manager King’s College London Tel 020 7848 6163 Email email@example.com
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 efficiency 2.Modulating the power input according to the motor loading.
Savawatt calculations Refrigeration 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 work The 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 typekWh/day Number of days Cost of electricity(£) Cost per annum (£) Number of freezers Cost per annum(£) minus 80°C17.6x 365x.1642.40x 74496.80 minus 70°C12x 365x.1438.00x73066.00 saving£1430.80
FWB -80°C to -70°C cost savings for 12 units Freezer typekWh/day Number of days Cost of electricity(£) Cost per annum (£) Number of freezers Cost per annum(£) minus 80°C17.6x 365x.1642.40x 127708.80 minus 70°C12x 365x.1438.00x125256.00 saving£2452.80
Drying cabinets FWB 5.118 one cabinet measured at 14.3 kWh/day Timers 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 CO 2. 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 = £649.70 By using a 12 hour timer we would save £323.96 per annum and 4.04 tonnes CO 2.