Alternative Energy

When you think of central heating you might gulp at the thought of what it might cost you to run a system. With household costs steadily rising from year to year it is wise to consider all of your options, and there ARE options, for keeping your home warm and healthy.

There is much talk of sustainability and renewable energy as being the way forward for humans and the way we live. What is renewable energy? Renewable energy is any energy that can be naturally replenished. This means using technology that harnesses energy from the sun, wind and water

How does this benefit you?

You might not change the whole world but you can definitely change your slice of the world by making better use of energy choices. By installing a central heating system that relies on renewable energy you will have the advantage of using a secure source. You will reduce your dependence on non-renewable energy. It will help you to reduce your family’s carbon footprint and best of all it will reduce your energy bill.

The Basics

Before having your central heating system installed it is wise to ensure that your home is as energy efficient as it can be. Making some changes as to how you use your appliances, when you use your lighting and water will help too.

Ask the experts – talk to us at Central Heating and find out what your options are for installing renewable technology in your home.

Some technologies have specific requirements for installation:

  • Solar PV and solar thermal depends on the way your roof faces.
  • Solar thermal, heat pumps and biomass require space inside and outside.

Having an understanding about what you want to achieve will help you experience the results you are after. For most people, saving money and reducing their carbon footprint are the main reasons they look at renewable technology.

Depending on why you are looking at a new central heating system you may find the following:

  • If you need to replace your boiler or central heating system, installing a new biomass boiler or heat pump will be your most cost effective option.
  • If your priority is to save carbon dioxide, you should consider a solar PV system.
  • If funds are limited then solar water heating will be your answer.
  • If you live in an isolated rural property with no mains electricity, you may get the most reliable off-grid supply from hydro or from a mixture of wind and solar PV.

Alternative energy options


A biomass system is a system that uses wood pellets, chips or logs to power central heating and hot water boilers.
A wood-fuelled biomass boiler could save you up to $1700 a year compared to electric heating.

Although carbon dioxide is emitted when the wood is burnt, the process is sustainable as long as new plants are planted in place of those used for fuel.

Logs can be cheaper than pellets, but costs depend on the wood suppliers in your local area, as they cost a lot to transport. If you have room to store more than a year’s worth of logs you can save money by buying unseasoned logs and letting them season for a year.


Air source heat pumps absorb heat from the outside air. This heat can then be used to heat radiators, underfloor heating systems, or warm air convectors and hot water in your home.
They are efficient at heating even when the temperature is as low as -15° C. Heat pumps have some impact on the environment as they need electricity to run, but the heat they extract from the ground, air, or water is constantly being renewed naturally

An air source heat pump will heat your home as well as your water. You will have lower fuel bills especially if you are replacing electric heating in your home. They have minimal maintenance requirements and can be easier to install than a ground source heat pump.

There are two types of air source heat pumps:

An air-to-water system distributes heat via your wet central heating system. They are more suitable for underfloor heating systems or larger radiators, which give out heat at lower temperatures over longer periods of time.

An air-to-air system produces warm air which is circulated by fans to heat your home. They are unlikely to provide you with hot water as well.


Ground source heat pumps use pipes which are buried in the garden to extract heat from the ground. This heat can then be used to heat radiators, underfloor or warm air heating systems and hot water in your home.
A ground source heat pump circulates a mixture of water and antifreeze around a loop of pipe, called a ground loop, which is buried in your garden. Heat from the ground is absorbed into the fluid and then passes through a heat exchanger into the heat pump. The ground stays at a fairly constant temperature under the surface, so the heat pump can be used throughout the year.

Unlike gas and oil boilers, heat pumps deliver heat at lower temperatures over much longer periods. During the winter they may need to be on constantly to heat your home efficiently. You will also notice that radiators won’t feel as hot to the touch as they might do when you are using a gas or oil boiler.


Solar water heating systems, or ‘solar thermal’ systems, use free heat from the sun to warm domestic hot water. A conventional boiler or immersion heater can be used to make the water hotter, or to provide hot water when solar energy is unavailable.

Solar water systems work all year round although when the winter months arrive you will need a boiler or immersion heater to see you through.

Once the system is installed you will notice significantly reduces hot water costs. This is because it runs on sunshine, and, sunshine is free.


Thermal Stores work very well in tandem with wood fuelled biomass boilers, heat pumps, wind and solar water heating systems.

A thermal store is a way of storing and managing renewable heat until it is needed. Heated water is usually stored in a large well-insulated cylinder often called a buffer or accumulator tank. It may also include an electrical heating element, such as an immersion heater.

A purpose-built thermal store can take inputs from a number of different technologies, provided it has been designed and sized to work with them all. It might store heat from a wood-fuelled boiler, solar water heating or a heat pump.

A thermal store can provide:

  • Space heating and mains pressure hot water.
  • Space heating only (which may be the case with a heat pump system).
  • Hot water only (common in the case of a solar water heating system).

The full potential of a thermal store is realised when it is used to store and manage a number of different heat inputs and outputs. For example, it lets you use your excess solar heat for space heating or to act as a heat pump pre-heat when this is used to supply hot water.