Household appliances consume a lot
of energy- on average a quarter of all the energy used in the house. Most
are not necessities but they make our lives easier (fridges, washing machines),
save us time (microwave ovens, dish washers) or simply give us pleasure
(stereos, radios, TVs).
So, its nice to have some appliances,
so long as we remember to chose carefully those that really are useful
and can justify their energy consumption and avoid those that just clutter
up the house costing us money.
In this section:
Minimising energy use
Fridges & freezers
Re-insulating fridges and freezers
MINIMISING ENERGY USE
The energy used by each appliance will vary enormously between different
homes- some people run their washing machines once a week, some people
run theirs every day. The really large energy consumers are air conditioners,
cooking stoves, and clothes dryers (each around 3 kWh per day). The second
level energy consumers are washing machines, dishwashers, fridges and
freezers, computers and televisions (each around the 1 KWh per day). The
third level energy consumers are appliances that are used regularly but
are low energy consumers (hi-fi, radios, clocks) and appliances that use
a lot of energy but are only used occasionally (vacuum cleaners, irons,
kitchen gadgets). Our approach has been:
Cut out the unnecessary appliances: We avoid a clothes drier
by drying clothes in the garden in summer and by using a drying rack
in the utility
room, which is in the hot
wet zone of the house.
Air conditioning is a needless luxury
in Europe- but air conditioning can be avoided in the hottest climate
by designing houses with high
thermal mass and stack
ventilation. Electric kettles are a remarkably high energy
consumer because they are used so often, often contain far more water
than is needed, and bring water all the way to the boil (which needs
three times more energy than heating water to bath temperature. We threw
ours out and in one move we cut our electricity use by 8%. We use a
kettle on the stove top and have taught ourselves how to fill it with
the right amount of water (one second of the tap on full is enough for
one cup). We kept two appliances that are heavy energy consumers and
certainly not necessities- a dish washer and a large chest freezer.
Many people live very happily without either. However we felt that their
usefulness justified their presence and we found ways to reduce their
Minimise the energy consumption of the heavy energy consuming appliances:
We replaced the electric cooker with a gas cooker. We connected
the dishwasher direct to the hot water and installed a thermostatic
valve for the washing machine. We bought a new efficient A grade fridge
and encased the chest
freezer in 100mm of insulation.
Live a low energy lifestyle: We have reduced our energy consumption
greatly by finding ways to reduce our use of high energy appliances.
We never run the dishwasher or washing machine on anything less than
full load, and we try to use them only at times when there is hot water
(in the summer we very rarely use them before 7 pm). We have a whole
range of strategies for low energy cooking including using the microwave,
the pressure cooker, and the "freecook" whenever possible. We switch
off everything when not in use to avoid the constant energy drain of
machines on standby (video recorders and tvs use almost as much energy
in standby as when they are working). Making a habit of such small measures
is an important part of living in an eco house (see Live
like Granny! ).
Like the vast majority of households we had a choice between gas
and electricity for our cooking. Gas is a fossil fuel and carries with
it all the problems of pollution and climate change. Some eco-houses have
electric cookers because they can generate their own electricity and want
to avoid fossil fuels altogether. However, for the normal house with standard
mains supply the best option is to avoid electricity whenever possible.
Electricity is extremely inefficient and a gas cooker has only a quarter
of the energy consumption of an electric cooker.
So we sent the old broken-down electric
cooker to the scrap yard and replaced it with a gas cooker. It was not
easy to find a good quality gas cooker. The cooker market is divided into
standard gas cookers at the cheap end of the market, and dual fuel (electric
oven and gas hobs) at the higher end. Almost all higher end makes (Smeg,
NEF, Blaupunkt) are dual fuel or entirely electric. The irony is that
very high end ranges and professional catering equipment have gas ovens-
but cost an arm and a leg.
We rejected the cheaper cookers as being
too badly made- and second hand ones are usually falling to bits. The
best option for a larger budget would be a reconditioned small model professional
cooker (4 burners and oven) which can be had for £800-£1,000. Lincat and
Falcon Dominator are the leading makes and are virtually indestructible.
They last a lifetime and never go out of production, so maintenance is
always possible. However, these only have single ovens and do not have
a built in grill.
So in the end we bit the bullet and opted
for a four burner Zanussi double gas oven and grill for around £600. Its
not great, but was the best available. The cheapest supplier with the
best technical advice was Buyers
FRIDGES AND FREEZERS
After heating systems and cookers, fridges and freezers are the largest
consumers of electricity. They use relatively little energy per hour but
because they are never turned off this constant drain adds up to nearly
a third of total electrical consumption in the average home. Consumption
rates vary enormously between different models. A new A energy
rating fridge will use 0.66 kWh per day. A 20-year-old fridge with a damaged
seal on the door can use 2kWh per day or more- three times as much!
It is tempting to do without fridges
and freezers altogether by buying fresh food and keeping it for short
periods in a pantry. However, there are also some environmental advantages
to keeping food in fridges; reduced wastage from spoiling, less frequent
shopping entailing less travel, saving energy by cooking and saving food
in bulk. The same arguments apply to freezers with one substantial bonus-
that having a freezer allows one to buy in bulk. This is an enormous advantage
is you live in a town but want to eat high quality organic produce or
support small producers. In the Yellow House, for example, having a freezer
enables us to store home
grown fruit and green vegetables, and to buy
organic meat, game and fish in bulk.
So, all in all, although we could live
without a fridge or freezer, they could be justified in an eco-house if,
and only if we minimised their energy consumption. We followed four strategies:
1. Creating alternative cool storage
We fitted a smaller fridge than many households and keep most of our
vegetables and preserves in cool storage spaces:
A ventilated "root cellar" under
the stairs, fitted with shelves. This is where we keep bulk grains,
vegetables and preserves. The space is vented to the passageway between
the houses. The access door in the living
room is thoroughly draft proofed.
The kitchen cool cabinet.
This large glass cabinet is also vented to the passageway, and provides
a cooler space for storing sauces, and perishable cooking ingredients.
sun porch- in the winter the temperature in the sun
porch is often cooler than the fridge. It is a good spill over space
for shopping and leftovers.
2. Buying the lowest energy models
In the last two years all new fridges and freezers have been forced
by the European Union to display energy rating labels. The savings from
the new A grade fridges are so high that they justify throwing out any
fridge that is more than 10 years old. This is one of the few times
when the best environmental option is to buy new.
The best configuration is a small larder
fridge and a separate chest freezer. Larder fridges are more efficient
than fridges with freezing compartments because the coils dont
ice up (and they dont need the tedious regular de-icing). Chest
freezers are more efficient than upright freezers because they lose
far less internal air when they are opened.
We replaced our poor condition old
fridge with a Bosch "A" efficiency new larder fridge which uses half
the electricity. There is so much price competition that a high efficiency
fridge need not necessarily cost more than a low efficiency one.
The CFC refrigerant in old fridges
and freezers is destructive to the ozone layer and a powerful greenhouse
gas. Never dump an old fridge or freezer- always take it to the council
tip or ensure that the supplier of a new fridge will removed your old
fridge and drain it properly. Most high street stores offer this as
a standard service. If the CFCs in your old fridge are released to the
air the harm they will do will far outweigh any environmental benefit
from a new fridge.
3. Re-insulate your current model
This is only an option for the dedicated do-it yourselfer. In theory
it should be possible to reduce energy use dramatically. We donated
the old freezer to a local soup kitchen and bought a good quality second
hand freezer for £100. George built a new insulating case around it.
Its electricity consumption fell by only 30%. This was less than we
had hoped, but enough to match the consumption of a new 'A' efficiency
freezer at far lower cost. (More on how to re-insulate
Even with the insulating case the freezer
accounts for a quarter of the house electricity consumption. We will
look at it again and see if there are ways of reducing it further.
4. Placement and use
Fridges should never be placed near cookers or hot water pipes- ours
is on the opposite side of the kitchen.
The only available place for the freezer was in the utility
room, but this was far from ideal for energy consumption.
A better location would have been somewhere shaded outside, such as
As usual, careful use can reduce energy
consumption even further. Opening and closing doors rapidly and ensuring
that the door has closed properly makes a big difference, especially
for the freezer. We allow any food for freezing to cool down completely
before putting it in. Whenever possible we put food that needs to be
defrosted in the fridge the night before. This avoids the health risk
of leaving defrosted food sitting around at room temperature and keeps
the fridge cool overnight. You need to allow 10 hours per kilo for defrosting
in the fridge.
One problem with our old second hand washing machine (£50 from a junk
shop) was that it took cold water and then used a lot of electricity to
heat it up for each wash. We decided not to throw it out and replace it
with a fancy model and took the cheaper option of installing a manual
thermostatic valve just above the washing machine in the utility
room. A few measurements with a thermometer established the
temperature of the valve settings (which were marked on the dial as numbers
between 1 and 9 and not as specific temperatures). When we wash we wait
for the optimum time for hot water (the end of the solar day in summer).
We then set the washing machine for the cool wash and set the valve for
the desired wash temperature (adding 7°C for warming up the machine).
Occasionally we need a really hot wash in which case we set the machine
to hot wash and the valve to maximum (depending on the electrical heater
to make up the difference). After five minutes, when the machine has filled,
we turn the valve to minimum so that the machine rinses with cold water.
This sounds complex and time consuming but we have found it easy to remember
and the valve has the advantage of being very flexible-working with any
machine and allowing full control over the wash temperature. It also means
there is one less thing that can go wrong with the washing machine- even
if its heater was broken or furred up (as often happens) we would still
be able to run it.
Whatever the marketing materials say, there is no such thing as a "low
energy" clothes dryer. The simple fact is that clothes dryers are major
energy guzzlers and have no place in a low energy home.
We therefore planned the house around
the need for clothes drying during the winter. The main drying racks are
in the utility
room to use the waste heat from the waste water tank and the
freezer. Damp air is extracted periodically through the fan above the
toilet, and through the laundry hatch leading into the bathroom (and hence
out through the bathroom fan). When we need further drying space we use
a rack on the mezzanine.
The heat at the top of the house dries the clothes and the winter stack
ventilation draws the moist air though the trickle vents in
the skylights. In good weather and in the summer
we use a washing line in the garden.
Like many people, we wanted a dishwasher for convenience and domestic
harmony. In theory a dishwasher uses more water and energy than hand washing.
In reality a lot of water is used in frequent small washes and rinsing
plates. We believe that a dishwasher can be far more efficient in its
use of water than soaking and rinsing in a sink.
The problem, though, is that dishwashers
gobble electricity. All leading makes of dishwasher are designed to take
only a cold feed and use electricity to heat up water for the wash cycle.
Some makes, such as Bosch, offer "low energy" models which have a heat
exchanger to preheat the incoming cold water, but still use electrical
heating. It is infuriating that there is not one leading make of dishwasher
that takes a hot water feed.
The simple solution to this is to plumb
the dishwasher directly into the hot water. The only disadvantage is that
this means that the machine rinses in hot water, but still worth it in
energy terms. We plumbed the dishwasher off the same hot pipe as the sink
in the kitchen
so that we could run the hot tap and get the water running hot before
turning on the dishwasher. It is important to do this otherwise the machine
fills with the cold water from the pipe and then wastes hot water on the
rinse cycle. All manufacturers of dishwasher discourage using a hot water
feed. I spoke to the technical departments of Bosch, Siemans and NEF,
and found that there is no problem with using hot water provided that
the incoming water is below 60°C. Their concern is that many households
have water tanks set absurdly high at 70°C or above and that water
this hot could damage the machine. There are good reasons for keeping
the water tank temperature to below 60° anyway - ours is set to 50°C
and never rises above 60° even on very good solar days (more
on tank temperatures...).
We bought a Siemans SF24200 45cm dishwasher
for £289. It was a cheap basic model without the "eco" features which
are not needed as they are mostly concerned with reducing the energy consumption
of heating. In practice we have found that it works very well and have
not noticed any problems at all with rinsing with hot water rather than
RE-INSULATING FRIDGES AND FREEZERS
The principles behind reinsulation of both fridges and freezers are:
1. Only re-insulate relatively new
machines (no more than 10 years old) in good condition with good quality
seals around their doors. In the case of older models it is definitely
better to cut your losses and buy a new machine.
2. Build clear and easy routes for
the flow of cooling air over the compression unit and condenser coils.
The easiest system is to raise the unit on blocks so that the air enters
under the front of the machine, over the compressor and up the back
over the condensor coils.
3. Box in all sides with good quality
4. The ideal insulation is 50mm thick
sheets of Celotex (or equivalent) expanded foam insulation with a shiny
foil facing. If necessary these can be sliced down the middle to create
thinner sheets, which must be attached with the foil facing outermost.
Only small pieces are needed and these can often be scavanged from building
sites, skips or rubbish dumps.
Although reinsulation will significantly
reduce the electricity consumption of a fridge or freezer, the amount
saved will depend on other factors; especially the efficiency of the
motor and the quality of the door seals.
REINSULATING THE FREEZER
Important note: Only insulate freezers with
external condenser coils (these are the
coils that get hot) Most chest freezers show plain white surfaces on all
sides because the condenser coils are built into the case. Any external
insulation around this case will prevent the condensers from working and
could be dangerous. Almost all upright freezers have external condensers
coils, though you may have to shop around to find a chest model with them.
1. Unscrew the brackets holding the
condenser coils. Gently bend the coil
where it comes out of the compressor and pull the coils and brackets
away from the back of the freezer. Insert no more than 25mm of expanded
foam sheet between the coils and the back of the freezer with the silver
side facing out and glue it in place. Reattach the condenser coil brackets
using strong glue or screws through the insulation and into the original
screw holes. Do not drill new screw holes into the case.
2. Glue 50mm (or more) thickness of
expanded foam to the underside of the freezer, as far as the rear edge
of the freezer, but being careful not to cover over any open area under
the condenser unit or around the condenser. There should now be a clear
route for the passage of air under and over the compressor and from
there up the back of the freezer.
3. Raise the freezer on wooden blocks.
This allows a generous air gap underneath for air flow. Place the freezer
so that the condenser coils are no more than 10mm from the wall.
4. Glue expanded 50mm (or more) thickness
of expanded foam along the sides of the freezer. These should extend
behind the freezer to the wall, boxing in the condenser coils on either
side with an insulated "chimney". Rising hot air from the coils will
now create a stack
effect drawing cool air from under the freezer, over the
condenser unit and up the back.
5. The finishing of the sides and front
will depend on the design of freezer. One possibility for an attractive
finish is to build a frame around the freezer, filling the frame with
insulation and nailing laminated hardboard, plasterboard or plywood
across the frame. A similar frame can be built around the door, filled
with insulation and covered with hardboard. If the door is also insulated
it is vital that the effectiveness of the seal around the door is not
6. Following the framing, as much insulation
as desired can be packed around freezer. An alternative technique would
be to create a far larger frame space and pack it with looser insulation
materials (polystyrene "peanuts" from packing, old polystyrene ceiling
tiles, and left over scraps of clothing or glass fibre). If you have
an upright freezer, a nice alternative would be to use a second hand
wardrobe with the same proportions as a case. You can insulate inside
the sides of the wardrobe and inside the doors to make a snug fit- cutting
off the back to ensure that the coils are well ventilated.
REINSULATING THE FRIDGE
If you have a freestanding fridge, it can be reinsulated in the same way
as the freezer. You could consider fitting it in a second hand cabinet
or wardrobe as discussed above. If you have a combined fridge and freezer
you could consider using an old wardrobe for the case for both.
If you have a fridge that is fitted under
the kitchen worktop, you will need to try a slightly different approach.
As with the freezer, air enters under the front of the machine, over the
compressor and up the back over the condenser coils. Providing that there
is a clear route for air to pass under the fridge and up through the countertop,
all remaining space around the fridge can be insulated.
It is therefore very important that there
is a permanent vent through the worktop for the hot air to escape.
1. Measure the fridge and the room
available for it. You need to allow 100 mm for the condenser coils at
the back and 30 mm air gap at the bottom. If you are building the kitchen
and have some flexibility, it is worth adding an extra 10-20mm to the
height of the workspace and allowing 50mm space on either side of the
fridge for the insulation. If you are buying a fridge, consider a small
model that allows as much surrounding room for insulation as possible
2. If you have sufficient space at
the back, insert insulation between the back of the fridge and the condenser
coils following the same procedure as for the freezer. Only do this
if it leaves 50mm air space on either side of the compressor coils.
Do not insulate the compressor compartment if it is too small to leave
30mm space around the compressor after insulation.
3. Most fridges are raised off the
floor by 30mm already. If the fridge does not already provide this much
air gap space, raise it on 30mm wooden blocks. After allowing for this,
there will probably be less that 50mm space remaining above the fridge.
Trim expanded foam to a thickness that would ensure a snug fit and glue
it to the top, being careful that the insulation does not extend over
the condenser coils. If you have a small fridge you may have enough
space to insulate underneath the fridge also. In this case, trim expanded
foam to fit, glue to the underside (being careful not to cover over
any open area under the condenser unit) and raise the whole unit on
30mm wood blocks.
4. Glue on expanded foam trimmed to
fit all available space on either side of the fridge.
5. Push the fridge back into place,
ensuring that there is a minimum of 50mm air gap between the condenser
coils and the wall.
6. Fit wooden trim around the door
to cover the exposed insulation at the front and side of the fridge.
Use screws so that it can be removed easily if the fridge needs to be
pulled out for repairs.
7. Install a vent or drill holes through
the worktop to allow waste warm air to escape from the back of the fridge.
8. To maintain efficiency it is worthwhile
to occasionally clean the condenser coils. Do this by unscrewing the
vent cover in the worktop and brush the coils with a long handled duster.