Solar News
Is your fridge up to speed?
Dave's Column - Fridges. Refrigeration can add a lot to your energy bill. Urban myths about power consumption of fridges and freezers, including that old beer fridge.
Urban myths:
a) 'My art deco 20 yr old beer fridge with 125mm thick walls, manual defrost and exposed condenser coils is efficient' - WRONG! a new auto defrost fridge with thin walls etc would use about 1/3 the power!
b) 'Upright fridges are very inefficient because all the cold air drops out when you open the door' - according to a USA uni study, door opening accounts for about 7 to 11% of the power consumption. Cooling air does not take that much energy. This can be minimised by keeping your fridge full & buying a fridge with some closed drawers/ compartments (my Electrolux has a conventional veggie crisper, but also a small goods drawer, egg & butter compartments).
c) 'Having the freezer on the bottom would be more energy efficient.' Not true, at least for the Electrolux range.
To save power, remember:
a) One large fridge is more efficient than having a separate fridge & freezer (or a beer fridge- sorry guys).
b) A large fridge uses more power than a smaller one but only a bit more- on similar models, power used is proportional to the surface area of the fridge. eg the 420 litre Electrolux uses 318 kWh/ year while the 520 litre uses 356 kWh/ year.
c) If you do have an old clunker with manual defrost- keep it de-iced as much as possible- eg defrosting once every few weeks if needed. Replace the door seal if it is compressed or perished- It should hold a sheet of paper when closed.
d) Place your fridge in a cool location out of the sun! Keep your fridge full.
e) If you live on solar, place any warm food or drinks in it on a sunny morning if possible.
f) If you buy a new fridge - look at the Star Label - it will list kWh per year- divide by 365 to get daily power- in fact they tend to use less than the suggested amount in a 'normal' domestic situation. RPC has monitored two fridges for a full year.
Why do I keep mentioning Electrolux? Well they are the most efficient and made in Australia in the 240 volt range!
Appendices
- watts = amps times volts
- 1000 Watts (W) = 1 kilowatt (kW)
- 1000 W or 1 kW x 1 hour = 1 kilowatt hour (kWh) or 'unit' and costs about $0.31
- 200 Watts x 5 hours or 100W x 10 hr = 1 kWh ( $0.31 on your power bill)