What’s Energy Efficiency?


What’s Energy Efficiency?

It is a true fact that we homeowners are always looking for ways to reduce our energy bills, whether it is turning off lights as we depart from a room, or closing shut an open door to retain heat. As little and as simple as these things sound – they work! Easy and cost effective measures around the home can have a significant impact on our energy bills as well as reducing our CO² emissions that contribute to global warming.

Heating Controls

Over two thirds of homes lack controls that would meet the current legal standards if newly installed, which means these homes are missing out, on a quite low cost way of making sure they get the best from their central heating system, keeping running costs low too.

An electronic timer or programmer


This decides when the boiler is able to run. Whenever the boiler is firing it is using energy and whenever the home is being heated to a temperature that is above what is outside, it will be losing heat to the world. In Spring and Autumn due to the weather conditions, there is no need for the boiler to be on all day, as the house will stay at a relatively warm temperature because of the heat outside. A 7 day timer is recommended to set different patterns for weekdays and weekends. Weekdays will probably need less heat for people working etc and weekends, there may be more activity in the household therefore requires more heating or the other way around. Some timers even allow day to day patterns to be set for each different day of the week. This can be useful for people working part time hours, or for when children get in from school etc. Setting the boiler to heat up when the energy is to be used makes more sense than the heating being on when no one is present. The energy is then being wasted and increasing energy consumption and bills.

Thermostat radiator control valves (TRVs)


Thermostat radiator control valves switch individual radiators on and off depending on how warm the room is and where the room is located in the house. For example, a room located above an unheated room (a garage) will require more heat to stay warm than the room above the kitchen or living area, as heat rises. With new individual radiator controls, they allow time and temperature to be set in separate rooms.

Weather compensator


Weather compensators or compensation controllers measure the temperature outside the building and vary the temperature of the water pumped into the heating system accordingly. A weather compensated system will provide building occupants with increased comfort levels whilst also reducing the amount of energy consumed as the boiler will fire less often as the system water temperature will be at a lower level.

In order to provide accurate indoor temperatures, the heat supplied to the building must equal the heat loss from the building. The greatest factor affecting how much heat a building requires is the outdoor temperature. Even in a well insulated place, heat loss increases as the outdoor temperature falls.

A boiler heating system is typically designed to always operate at the highest temperature possible to match a buildings heat loss on the coldest days of the year. Most United Kingdom locations have less than 10 days in a year that actually require this high temperature.

So what happens when the outdoor temperature is relatively mild? The heating system delivers too much heat, therefore overheating the space and costing more money. In commercial or apartment styles buildings, where occupants do not directly pay for heating bills, energy costs increase more as occupants open windows to compensate for overheating conditions.

Weather compensation is a control strategy that continuously adjusts heating system supply water temperatures to compensate providing more heat when its colder and less heat when its warmer. For most of the heating season, the control saves energy by operating at a lower temperature, reducing the amount of heat lost.

Green Energy Generation can offer a wide range of weather compensating controls that operate single boilers, multiple boilers or a mixing device to ensure the proper water temperature is delivered based on the outdoor temperature. These controls are also equipped with additional features such as the automatic boiler differential, to ensure the boiler gets a long efficient on time as well as off time.

These controls not only provide typical savings of 5% up to 30% but also improve comfort to the building occupants by delivering the right amount of heat.


  1. Energy Saving Light bulbs – save £5-10 per year with a cost recovered in about 6 months
  2. Hot water tank insulation – save £10 per year and the cost is recovered in 1 year
  3. Draught proofing – save £35 per year with the cost recovered in 3 years
  4. Heating Controls – save £50 per year with a cost recovered in 2-5 years
  5. Double Glazed Windows – save £40 per year and the cost is recovered within 5 years
  6. Loft Insulation – save £80-£100 per year recouping the cost in 2-6 years
  7. Cavity Wall Insulation – save £130 per year and recoup the cost in 3 years
  8. Replace an old boiler – save £120-£200 per year and recoup the cost in 4-5 years