Changing habits to save energy 

Heating and heat retention

Turn down the thermostat

The lowest comfortable temperature for most people is between 18⁰C and 21⁰C.  If it feels warm enough, try turning down the thermostat by 1 degree.  It can always be turned back up if it becomes uncomfortable.  Consider setting a lower temperature for the morning (a more active period) than for the evening when one is likely to be more sedentary. The Energy Savings Trust suggests dropping 1-degree from 22⁰C and 21⁰C will save the average householder about £90/year. 

Only heat rooms in use.  (Thermostatic radiator valves have a “frost-free setting” indicated by a *, ideal for rooms that are unused for several days.)

Turn the heating off when going out.  And when on holiday, the “holiday” setting on the thermostat controller works so that the heating and hot water come on just ahead of returning home.  In winter, the thermostat can keep the house frost-free by setting a minimum temperature of 5⁰C – 10⁰C.

When is it best to heat the house?

Generally, it is best to set the central heating system to come on about 30 minutes before rising in the morning and set to switch off about 30 minutes before going to bed.  Using a boiler, having the heating on all day rather than only when it is required will use more energy, create more CO₂ and cost more money, than having the heating on when required.  (Note: there are benefits in having the heating on all day, if using a heat pump).

Shut curtains and shutters and draw down blinds at nightfall

Using blinds, curtains and shutters can significantly reduce heat loss through windows.  Historic Environment Scotland (HES) reports that shutters alone can reduce heat loss through windows by up to 51% and a combination of blinds, curtains and shutters can reduce heat loss by 62% – almost as much as secondary glazing. 

HES states that full-length, lined, and well-fitted curtains will reduce draughts and reduce heat loss by up to 14%.  However, watch that the curtains do not obstruct radiators.  If that is a problem, consider installing a shelf above the radiator and altering the curtains so they only drop to the shelf rather than the floor.

Electricty usage 

Switch off appliances

Appliances such as TVs and computers use electricity when on “Stand-by” mode.  The Energy Savings Trust advises that almost all appliances can be switched off completely at the plug without upsetting their programming.   The exceptions are satellite and digital TV recorders which need to keep running to record programmes.  The Energy Savings Trust states the annual saving is £40/year when appliances are switched off completely.

Timing heavy use of electricity

Some energy companies offer discounts for electricity used at off-peak times (such as Sunday afternoons), or credits for not using electricity during times of very high demand.  Households with solar panels will be able to access cheap “home-produced” electricity during the day either for direct use in the home or to recharge batteries.  These incentives aim to help maximise use of renewable electricity and minimise use of fossil fuels.  Sometimes energy companies announce incentives at short (24 hour) notice.  You need a smart meter and require to sign up for these incentives.  By planning washing or batch cooking so they are done in the discounted, off-peak times will save money.  Likewise avoiding these activities when a period of high demand on the grid is announced, will attract a cash credit.

Turn off lights

Lighting accounts for about 11% of the average UK homes electricity consumption. Switching off lights on leaving a room helps to reduce energy consumption, carbon footprint, and electricity bill. 

Other steps to take are:

• Use energy efficient lightbulbs (See ‘Fixtures and Fittings’).
• Consider how many lights are needed in a room. 
• Use sensors or timers on external lights to ensure that they are only on when required.
• Consider using lighter or transparent shades or fittings.  Dark lampshades absorb some of the light the bulb emits.
• Regularly clean lamp shades and fittings to maximise the impact of the light emitted by the bulb.

Consider how a washing machine is used and minimise use of the tumble dryer

The Energy Savings Trust states that the cost of running a washing machine, dishwasher and tumble dryer accounts for about 14% of the typical home energy bill.  These machines use electricity to heat water and air, and to operate.  Consider the following to reduce energy consumption, reduce carbon footprint, and save money.

• Can some clothes be washed at 20°C?  All washing machines bought since 2013 have a 20⁰C option on the control panel to help save energy.  “Which?” reports that turning the cottons programme temperature down from 40⁰C to 20⁰C reduced running costs by about 60% as less energy was needed to heat the water.  The cleaning power was slightly worse at 20⁰C but switching to a liquid detergent helped and was fine for everyday washing.  Using a longer (2+ hour) cycle may give better cleaning power while still saving energy compared to a short 40⁰C cycle.  The machine uses less energy turning the laundry over than heating the water.  “Which?” strongly advises running a monthly maintenance wash with a washing machine cleaner when washing at low temperatures.
• Washing at 30⁰C uses 38% less energy that washing at 40⁰C.  The 30⁰C programme is often recommended for delicate fabrics such a wool and silk.
• The 40⁰C programme is better for cleaning tough stains than lower temperatures.
• There is little benefit in using a 50⁰C programme as “Which?” found most stains were removed at 40⁰C and the higher temperature uses much more energy.
• While “Which?” found that a 60⁰C wash was best at removing greasy stains and is ideal for bedding and towels, it costs 50% more to run than a 40⁰C programme.  A 60⁰C wash is often recommended to kill, bacteria and other micro-organisms.  However, not all bacteria and viruses are killed at 60⁰C.  “Which?” recommends choosing a good detergent (see their current recommended products), treating stains and washing at 40⁰C to obtain a good wash and save energy, carbon and money.
• Run full loads in the washing machine, or dishwasher.
• Minimise use of the tumble dryer.  “Which?” recommends (i) running an extra spin cycle before tumble drying to reduce the time the dryer will be on, (ii) untangling the laundry before drying to allow the air to circulate, and (iii) cleaning the lint filter after every use. 
• Could washing be hung on a rack or pulley, or outside in better weather?

Maintain appliances

Fridges, freezers, and tumble dryers all need regular maintenance to ensure they operate effectively and efficiently.   The appliance’s manual will list the manufacturer’s specific recommendations for maintenance. However, consider the following to reduce energy consumption.

• Regularly defrost a freezer so that the condenser does not have to work as hard.
• Clean the condenser coils of the fridge and freezer.  These are usually found at the back of the appliance and so it will be necessary to pull it away from the wall and unscrew the grate that usually covers the coils before dusting them to remove dirt.
• Which? advises cleaning the lint filter of tumble dryers after every use.  Fluff from your laundry can block the filter and prevent the hot air circulating effectively.

Cooking appliances

Cooking – ovens, microwaves and kettles

The Energy Savings Trust states that the cost of running kitchen appliances such as hobs, ovens, microwaves, and kettles accounts for about 3 to 4% of the typical home energy bill.  Air fryers, slow cookers, bench top ovens and other similar appliances use less energy to heat up and hold the required temperature than a large oven.

Switching from a gas hob to an electric hob will reduce a carbon footprint through replacing gas, a fossil fuel, with electricity which is increasingly obtained from renewable sources.  (And it is a less expensive first step to reducing gas usage than replacing a gas boiler.) While gas hobs were favoured for their immediate heat response and precise temperature control, electric hobs, particularly induction hobs, are more energy efficient and easier to clean; however, they may require special cookware to work effectively.  Burning gas in the kitchen emits more air pollutants in the home than electric hobs.

Consider the following points to reduce energy consumption when cooking:

• Using an air fryer, bench top oven or other similar appliances, rather than an oven when cooking for one or two people.  The smaller appliance uses less energy to heat up and hold its temperature than the oven.
• Microwaves are more efficient than ovens to reheat food as they only heat the food rather than the air inside.
• Batch cooking makes best use of the larger capacity of an oven.
• A slow cooker may be a more efficient alternative to an oven as again the energy is concentrated on cooking the food rather than heating air. 
• Keep the lids on pots when cooking.  This uses 10% less energy, the food will cook more quickly, and the kitchen will be less steamy.
• Try not to overfill the kettle.  Why boil water that is not going to be used?

Hot water usage

Heating domestic hot water to an excessive temperature will increase energy usage and waste money.  Setting the hot water thermostat to a temperature of between 60°C and 65°C is the usually accepted range.  That temperature could be reduced but bear in mind that below 50°C there is an increased chance that harmful bacteria may survive in the system.

Ensure that the hot water cylinder, if fitted, is adequately insulated to prevent heat loss.

It is generally considered that use of a shower is more energy efficient than use of a bath, though that depends on how they are used, and the energy source used to provide the hot water.  An electric shower is more expensive to run than a shower where the water is heated by gas.  A typical bath might use between 100 and 200L, whereas a 10-minute shower might use up to 150L.  Using a timer to limit the length of shower will help limit water usage. Some shower heads are more efficient than others.  Installing a low-flow shower head or aerated shower head will reduce flow rates considerably.

REFERENCES AND SOURCES:

Energy Savings Trust – https://energysavingstrust.org.uk

Nancy Birtwhistle (2022). “Green Living made easy”: London: One Boat an imprint of Pan Macmillan.

Historic Environment Scotland, Guide to Energy Retrofit of Traditional Building – www.historicenvironment.scot/energy-retrofit

Which? – https://www.which.co.uk