Advice advocated by the Local Government Energy Doctor’s scheme

(Note that this scheme is no longer taking applications.)

Low-Cost Easy Retrofit Resource Efficiency (or Cheaper Easy Solutions)

Measures include:

• Electric heated throws
• Draught proofing windows, doors, letterboxes, and chimneys
• Hot water cylinder insulation jackets
• Reflective radiator panels
• Secondary glazing film
• Portable solar generators
• Electricity consumption monitors
• Thermometer cards
• LED lights
• Smart plugs
• Water saving measures including:
  • Shower timers
  • Aerating shower heads
  • Toilet cistern bags

General Advice, from the Marlow Energy Team

• Assess the needs of your home’s occupants.

Everyone’s level of warmth and comfort is different, and temperatures around the house will depend on the external weather. How warm you feel will also depend on how active you are. If you are busy and moving around you are less likely to feel the cold, but if you sit still reading, watching TV, or working, you may feel colder after a while.

Windy days are likely to increase the penetration of draughts into your living space and sometimes make it hard for heating systems to maintain adequate temperatures. Older or more sedentary folks may need higher temperatures or more blankets than younger, more active folks.

• Keep your body warm rather than heating the whole house.

Wearing several, thinner, layers of clothing may be more effective than one thick layer. Training your children to wear adequate clothing inside in winter can also save on energy bills! If you are sitting still for a longer period, use a blanket or an electrically heated throw. In some cases, radiant heaters may be more energy-efficient than convector heaters.

• Concentrate heat in spaces you use.

Use doors, radiator valves, thermostatic valves, or heaters to heat the rooms you are using rather than the whole house.

• Remember that electricity costs more than gas for heating (unless you are using a heat pump).

At the moment, in the UK, gas is the cheapest fuel to heat a house. Electricity costs are 3 to 4 times the cost per kWh of energy. So, if you use grid electricity directly for heat, it will cost you more than gas.

However, sometimes heating one room with electricity is cheaper than using gas to run a heating system for the whole house. An energy monitor is available from energy supply companies on request. It is digitally connected to a Smart Energy Meter which the supply company will fit to your electricity and gas supply. With smart gas and electricity meters a monitor can help you work out when you are using gas and electricity and how much you are using at any time of the day. This can help you to decide how best to manage your energy use.

• Exclude draughts.

Keeping windows closed and draughts out are easy and practical first steps in heat management. Most older UK built, houses are draughty. Windows with “trickle vents” can cause draughts. Whilst trickle vents are a good idea in summer and help maintain necessary ventilation all year round, they can cause significant energy leaks in windy or very cold weather.

To reduce energy loss, it is helpful to draught-proof windows, doors, letterboxes, and chimneys. Using your hands to feel for draughts around doors, windows and letter boxes is a simple and effective way of tracking down significant draughts. There are now companies who can undertake tests which are more definitive, at a cost. Cheap temporary improvements can be made using draught- excluding tapes over gaps and secondary glazing film (plastic sheet) over single- glazed windows. Simple draught excluders under doors and in letter boxes can also help. An open chimney flue can cause significant draughts in a room with a fire place and no fire. Chimney balloons or chimney sheep are a reasonably simple, low-cost method of blocking a flue to stop the draught from an open chimney. They are readily removed and must be removed before lighting a fire! Look online or in DIY stores for all of these items.

Maintain necessary ventilation

• As draughts are excluded and windows and vents shut to save heat energy, it is important to ensure adequate ventilation is maintained. Gas boilers and fires require a source of outside air and should be fitted near an open vent. Carbon monoxide is a poison that can build up if gases from boilers and fires are not exhausted from the house. Fit a carbon monoxide alarm near gas boilers or fires.
• Build-up of moisture in the home is also a problem and can lead to mould if allowed to continue. People, pets, washing, drying clothes and cooking all generate steam or water vapour which increases moisture within the home. Moisture alarms are available to buy. Occasional window opening for a brief period during the warmer parts of the day can help reduce moisture build up without losing large amounts of energy, especially for kitchens and bathrooms. External humidity is high during rain, fog and mist and is not a good time to open windows to reduce moisture. External humidity meters help to determine when to open windows.

Insulate your loft

• The majority of heat loss from a poorly insulated house is through the roof. The UK Government advises that a minimum of 270mm of mineral wool or fibreglass should be used in lofts. Check how deep your insulation is and build it up to 270mm or 300mm. This is not a very expensive upgrade and can pay for itself in a few years by cutting heat energy bills from the moment it is installed. Most UK homes have been built with naturally ventilated roof spaces so concentrate on insulating the ceilings of the living space below the loft. Sealing the loft space and insulating the underside of the roof should only be undertaken in special circumstances. If in doubt, ask a professional, as some unscrupulous insulating companies have been known to cause serious problems to householders by applying insulation in a way which can damage the property or cause problems with mortgage lenders.

• When insulating loft space make sure water pipes in the loft, or outside insulated walls, are properly lagged to prevent freezing.

Update your heating controls

• Management of heating controls is vital to good energy performance. This could be as simple as checking the programming to ensure set temperatures make sense and on/off times match your lifestyle. Why heat your house whilst you are out when frost protection is all that is required?

• Install thermostatic radiator valves and set them to suit the room use. Modern control systems are now available that can be adjusted using phone apps for families with variable heat demands. When coupled with Wi-Fi controlled radiator valves, different rooms can be set to heat at different times, e.g. switch off bedroom heating during the daytime. If you do choose not to heat a room, remember to shut the door so that it doesn’t draw heat from the rest of the house.

Check insulating efficiency of windows, walls, doors, and floors.

• Where possible replace single glazed windows and old draughty frames. Drawing curtains closed as temperatures drop, e.g. in the evening, will reduce energy loss through the windows they cover. Insulated (heavily lined) curtains or blinds can help reduce heat loss more than unlined curtains when drawn. Replacement windows with double glazed glass units with thermally insulated window frames will reduce heat loss but are more effective when sealed well between the frame and brickwork. Secondary double glazing is a possible solution for complex windows or listed buildings.

• Heat loss through walls can be a significant problem, particularly in older houses which were built without cavity walls. Cavity walls grew in popularity from the late 19^th Century / 1920s but were rarely insulated until the 1970s. Insulated cavities were compulsory in the UK for new builds across the UK from the 1990s. Some homes have been retrofitted with blown cavity wall insulation, but in some cases the insulation blown in has deteriorated, causing loss of insulation, or damp. Internal or external wall insulation is being used more commonly now, especially for houses with solid walls, but this must be carried out by reputable companies and can be expensive.

Details of insulation required for new builds or renovations are available in Building Regulations and on some UK Planning Portals.

Underfloor insulation has been required in new builds since 1976 in the UK. Retrofitting underfloor insulation is frequently expensive but can be done as part of a general renovation and is required if more than 25% of a floor is renovated.

Smart or intelligent meters can be fitted to your gas and electricity supplies. Energy supply company regulations mean the company has to provide a householder with a smart meter if requested, by the householder, to do so. Energy supply companies vary in how quickly they will fit a Smart Meter. The Smart Meter means the supply company can monitor consumption via internet and should be able to bill more accurately. The Smart Meter provides the householder with better information on energy use and provides access to advantageous energy tariffs. A Dumb Meter is one which must be read by the householder, or by an employee of the energy supply company by visiting the meter and making a reading.

*An Advanced Tariff is one that charges different prices for energy depending on the Time of Use. These tariffs can be applied to both energy used (Import) and energy generated (Export) based on consumption every 30 minutes.

How to save money with a smart meter

There are 3 ways to reduce your energy bill:

1. Use less energy (manage your usage using the displays, home insulation)
2. Pay less for the energy you import (Advanced Tariffs)
3. Generate your own energy (Solar Panels)

Or a combination of these (consuming electricity at expensive times of day after filling up batteries at cheaper times or from own generation).

Heat pumps are more than 3x more energy efficient than traditional boilers, meaning they’ll substantially reduce the carbon footprint of your home. Because they run on electricity, there’s potential to make bill savings by using smart tariffs with cheaper off-peak rates.

The government is offering a grant of £7,500 in England and Wales to help cover the cost of installation, as long as the installation replaces a fossil fuel heating system (gas or oil) and the installer is MCS registered. Check the detailed requirements of the Boiler Upgrade Scheme grant.

• A qualified installer will usually provide an estimate based on information you can provide about your house, e.g. number of rooms, levels of insulation etc.
• To get an accurate quote your house should be surveyed to check number and size of radiators and the heat retaining properties of the house (insulation, windows, doors etc).
• They will also check what space is required inside and outside for the equipment required with the heat pump system.
• Most installers will charge a few hundred pounds for the survey and updated quote. The survey fee may or may not provide an Energy Performance Certificate and may or may not be refundable if you decide not to go ahead with the installation. Check before buying.
• Installing a heat pump at most houses is a “Permitted Development” depending on where the heat pump will be located. This means that provided the installation meets the requirements of Permitted Developments no planning permission is required.
• Using a heat pump for home heating in a reasonably will insulated house, instead of a gas, oil or coal fired boiler, will make a dramatic saving in carbon dioxide emissions.
• Although a heat pump is far more efficient than a gas or oil boiler in terms of kWH of heat it provides to your house per kWH of electricity, gas or oil consumed, a kWH of electricity in the UK is generally around 3 times the cost of a kWH of gas. Therefore, operating a heat pump will not necessarily reduce your energy bill for heating. However, UK government has indicated that it will reduce electricity costs per kWH and heat pump electricity tariffs are available which can save money by using electricity at off peak times.

Qualifying installers can be found on various websites (linked below).

• A heat pump will dramatically reduce carbon dioxide emission or the carbon footprint of the house, as electricity is increasingly being produced from non-fossil fuel sources, e.g. wind, solar and nuclear power.

• Heat pumps operate by extracting heat from the air (or from the ground) and moving it into the house. The operating principle is the same as your domestic fridge or freezer, only instead of pumping heat out of your fridge a heat pump pumps heat out of the air (or ground) and into the house.

• They can be used with water based central heating systems based on wall mounted radiators, but it is often necessary to upgrade some of the radiators, or enlarge them, to provide the necessary heat transfer area. This is because the hot water from a heat pump is not as hot as hot water from a gas boiler. However, this is not a problem, as in both cases the hot water is much hotter than the house or the hot water needed for washing.

• For a heat pumped system to perform well, the house needs to meet a minimum level of insulation to retain the heat that is produced.

• If your heating uses a heat pump, the efficiency of the heat pump roughly rebalances the cost per kWh heat. This is because the heat pump generates up to 3 kWh of heat for each kWh of electricity it uses.

• Opinions vary, but at current gas and electricity prices a well-designed heat pump system in a reasonably well insulated house will cost a similar amount a year to run than a gas boiler-based system. By using one of the cheap Heat Pump electricity tariffs now available a heat pump can save a few hundred pounds a year. If electricity prices continue to fall relative to gas prices this saving should increase.

• However, even with current government incentives, replacing a gas boiler with a heat pump is likely to cost several thousand pounds.

• If a heat pump system is not possible for your house, make sure that you are using a condensing, gas boiler and not setting the flow temperature too high. A condensing gas boiler is far more efficient at turning gas into heat than an older style (non-condensing) boiler. A modern condensing boiler can be 90 to 98% efficient, whereas on old non-condensing boiler might be 70 to 80% efficient, with some as low as 55% efficient. Hence, they should save 10 to 20% or more of your gas bill depending on how old and inefficient your boiler is.

• Also make sure you have your boiler serviced regularly by a qualified Corgi plumber. Minor checks and adjustments at the service keep the boiler safe and ensure it is running as efficiently as possible.

Why have a solar installation on your house

• Solar panels generate electricity from the sun. Energy from the sun is free. You just have to have the equipment to convert it to energy you can use. Each time you use a kWH of energy from gas or oil you must buy another kWH of gas or oil for the next kWH. You must continue to pay at whatever the current price is, as you use fossil fuel energy. Solar energy remains free.
• The complete solar installation is free of VAT in the UK at the time of writing. This includes any battery that is installed at the same time.
• Solar panels are getting cheaper and more efficient all the time, and many have 20 year or more guarantees. The installation may reduce in efficiency by 1 or 2% per year and will eventually need replacing. By then much more efficient equipment is likely to be available.
• Solar panels produce more electricity on clear days with sun and since we have longer sunnier days on the summer that is when you get most electricity from the panels. Solar panels will produce also electricity on cold winter days if they are sunny but for a shorter period as the daylight hours are shorter and the sun is lower in the sky.
• Solar panels produce maximum electricity in the middle of the day when the sun is highest, so it makes sense to think about having a battery to store the energy for use in the evening.
• South facing sloping roofs produce more solar energy but east and west facing roofs produce 80% of that energy. Even north facing roofs produce 50% of the energy.
• Roofs which are overshadowed by buildings or large trees will see less sun and therefore may not be the best roof for panels installations. Shadow becomes less of a challenge with new panel developments and by use of micro inverters. However, micro inverters can introduce a point of failure in the system which some installers will warn against.
• Flat roofs can be used for installations and are covered by planning rules. Usually, a mounting system is required to tilt the panels to the correct angle and ensure they are not damaged by wind.
• Standard sized panels approximately (1.7m by 1.2m) can weigh over 20 kg each and mounting system also adds weight. Installers are supposed to review the roof structure to ensure it is strong enough to support the installation. If in doubt, ask for s structural engineer to review to structure.
• You can install solar panels in most roofs without planning permission as long as the installation fits within the parameters allowed for a “permitted development”. No planning permission is required for a Permitted Development. Permitted development for Renewable Energy on domestic residences is defined by the Town and Country Planning Act, Part 14. Most installers will understand this, but it is the homeowner’s responsibility to apply for planning permission if it is required. In Bucks the Planning Portal allows you to answer several questions online to determine if the development you are planning requires planning permission.
• If your building is listed, you are in a protected area or the installation does not fit the parameters allowed for permitted development, you may still get permission but may have to make a planning application.
• With the right equipment you can sell electricity you don’t use back to the grid.
• Solar thermal panels are still available and are the most efficient means of heating hot water using solar energy. However, they require a circulating hot water system to flow from the panels to your hot water tank. The plumbing can be hard to achieve depending on the layout of the house. Thermal panels can also be Permitted Developments.

Getting a Quote for a Solar Installation

• Most installers can give you a preliminary quote as long as they have your address. They look at satellite images and maps to check your roof, what space there is for panels, whether the roof is overshadowed, and the orientation.
• Prices can vary significantly and the equipment offered can also vary, so we recommend talking to at least 3 installers to see how the quotes vary and which installer you like best.
• We recommend that you deal with installers that are MCS (Microgeneration Certification System) accredited as the certification checks their capabilities and gives them rules to work by which help protect you from poor installations and exaggerated sales pitches.
• Check installer references to see if they are likely to give you the service and installation you want and will help you understand the design and use the system they provide.
• A solar installation is a significant purchase, so don’t be afraid to ask questions and get revised quotes where required. Make sure the price you finally agree provides all the equipment and services you require.
• Short list the quotes you have had and select the quote you are most comfortable with as the leading offer. You may have to pay a few hundred pounds for a physical survey or your property to ensure that the preliminary design and pricing suites your house. This is a good time to be available and to ask questions about layout etc.
• Following the survey check that your price includes any changes required by the survey.
• Some installers can access finance for installations but check any finance deal has reasonable interest rates and terms and conditions and is overseen by the FCA (Financial Conduct Authority).
• The District Network Operator (DNO) is the company that maintains the electricity grid in your area, and they need to give permission for a solar installation as it can affect the local grid. Most installers will handle the bureaucracy, will design your system to meet the DNO requirements and get approval on your behalf. It may take a few weeks to get approval. It is unsafe to proceed without DNO approval.
• Some companies used to install panels on home owners’ roofs and allow the home owners to use electricity generated. If you are considering a similar scheme, be aware that there were some significant problems with some contracts when it came to selling the house and possibly equity release schemes. Take legal advice.

Options to decide during the quote process

• The vast majority of panels and solar equipment installed in the UK domestic market is manufactured in China. It is possible to get European manufactured equipment, but it could be up to 30% more expensive. This is due to the scale of Chinese solar manufacturing reducing the price. Some installers have preferential supply agreements and training with particular suppliers. They may not be willing to buy equipment from others.
• European batteries and inverters are available, but components may still be manufactured in China.
• Check you are being offered equipment with good references and guarantees.
• There are subtle differences in the efficiencies of panels made by different manufacturers, the guarantees and UK support offered by the manufacturers.
• Panels are generally installed on existing roofs by fixing rails to the roof and mounting the panels on the rails. The rail is supported by metal hooks which pass under tiles to attach to the roof. Some installers suggest “notching” the tiles to allow the tiles to lie flatter after installing the hooks. It cost more but there is an argument to suggest it may reduce storm damage to the roof in the long term.
• Check the installer knows the type of tiles or roof you have and that they quote accordingly.
• Bird guards are available to prevent birds taking up residence under your solar panels. There are several types of guard, but they all block the gap between the panels and the tiles to stop ingress. If you want a guard, choose the type you want on your roof.
• On new builds or for visual reasons, panels can be set into the roof on trays. On new builds, or major renovations, this can save on tiles required. On existing roofs, tiles are removed to fit the trays and panels. The use of trays and cutting the tiles to suite is usually more expensive than mounting on rails above tiles.
• If you install a battery at the same time as solar panels your installer should ask if you want to maximise your own use of the solar electricity by charging your battery from the panels when power is available. Alternatively, you can maximise export of power to the grid.
• Devices can be purchased as part of a solar system, to use excess solar power to heat water if you have a hot water tank. The hierarchy of priorities of charging a battery, heating water or exporting to the grid can be set up with in the systems software during commissioning. It can also be adjusted later, if necessary.

Installation of Solar Systems

• The installation itself is usually done within one to three days for a home, depending on the size of the installation and the size of the team. Safety scaffolding is generally required for a roof installation. It will be erected before the solar installers come and taken down after they have finished. It might be in place for a week or more.
• The installation work will mainly take place on your roof and close to the incoming power supply and distribution board. Some access to the inside of your house may be needed to run wires to connect the system together, e.g. through the roof space.
• It is sensible to check your roof does not need repair before panels are installed. Access to the roof under the panels is more difficult and expensive once the panels are in place.
• If you choose to have battery installed at the same time as your panels, discuss the location of the battery and inverter installation with your installer. The installation will need to connect to incoming electricity equipment; inverters can issue a high-pitched hum when operating; batteries function better above 5 ⁰C and below 35 ⁰C, depending on make.
• Battery installations within the roof space are no longer recommended.
• Make sure they quote a fully inclusive price, you know what equipment you will get for the price quoted, meaningful guarantees and good quality equipment which has good reviews and guarantees. 
• Most systems come with a phone App these days. It is useful to have your installer show you how to use it. It should tell you how your system is working and help you understand how the seasons and weather effect its operation.
• Intelligent electricity meters are not a requirement for a solar installation, but they can help you to make the most of your system.
• Power suppliers are required to install intelligent metering if you request it. Some take longer than others.
• Intelligent metering can help you make the most of flexible tariffs or off-peak electricity pricing.

Maintenance of Solar Systems

Although panels are often guaranteed for 20 years or more, inverters tend to be guaranteed for 10 years. Hence be prepared to replace your inverter during the operating life of the panels to keep the system working.

Most installation self-clean during rain. The lower the angle of panel inclination the less efficient rain will be at cleaning it. Occasional cleaning can help improve panels efficiency if they are getting covered with leaves, dust or bird droppings. Most window cleaner with long window brushes will clean panels for a fee.

Marlow Energy has compiled a list of non-commercial organisations that offer advice and information to householders to reduce energy use and save money.

• Energy Saving Trust (EST)
• National Energy Foundation (NEF)
• Local Authority Delivery (LAD2)
• Centre for Alternative Technology (CAT)
• Gov.UK Find ways to save energy in your home
• DraughtBusters Reading

The list below is of organisations that offer grants which may save energy use, CO2 emissions, and money! Check the qualifications required in each case, as some grants and support are only open to householders on income support.

• Energy Saving Trust

• National Energy Foundation, Green Homes Grant LAD

• Government funded schemes, domestic retrofit

• Warmworks Green Home Grants

• ECO (Energy Company Obligation)

• Warm Home Discount

See the Citizens Advice page. MCS Certification covers most of the low carbon technologies available for homes.