Until quite recently, the automatic choice for heating your home was an oil or solid-fuel boiler. Things have changed in the world of home heating and It will be illegal to install an oil boiler from 2022. Gas boilers will be banned from 2025 in all new builds. However, a replacement for existing oil and gas boilers is also being planned.
So, if fossil fuels are being phased out, what is the best heating system for your home? Whether you’re planning a new build or retrofitting an older house, your heating system of choice needs to be:
- cost-effective to install
- efficient to run
- a reliable source of comfortable warmth
Here are some alternative options below;
Along with solar panels, heat pumps are probably the most popular option for anybody looking to install an energy-efficient heating system in their home. It’s easy to see why: A heat pump generates about 4KW of thermal energy for each kW of electricity it consumes, which equates to a 300% efficiency. What does that mean?
Well, a condensing gas/oil boiler can only manage about 90–96% efficiency, and a conventional gas/oil boiler can only reach about 70–80% efficiency.
How does a heat pump work?
A heat pump uses electricity to extract heat from outside and transfer it indoors at a higher temperature. It contains a fluid that absorbs the heat from the air or ground outside your home and is then compressed and raised to a suitable temperature. The heat from the fluid is then transferred to the water in your heating system, including radiators and underfloor heating, as well as your hot water tank.
The energy used to power the electric motor that drives the compressor is relatively low compared with the renewable heat the pump extracts from the environment. This makes it highly energy efficient.
Ground-to-water heat pumps are more efficient than air-to-water systems. They extract the heat stored in the ground by heating water in a network of tubes buried underground. They are costlier to install than the air-to-water versions (due to the excavation and space required). Both systems work optimally with underfloor heating or large radiators because of their lower operating temperature requirements. Good insulation and draught-proofing are key requirements.
Heat Pump Costs & Benefits
Heat pumps do cost more than conventional fossil fuel boilers. If you choose this low-carbon heating option, however, the SEAI can provide a grant of €3,500 towards the cost of installing a heat pump system in homes constructed before 2011.
For new builds, the payback with a heat pump should be no more than three to five years. The marginal cost of installing a heat pump, appropriate cylinder, and potentially larger radiators is comparable to the fossil fuel alternative. This is because a gas boiler plus connection to the grid and associated infrastructure, or an oil boiler plus a tank, need the addition of photovoltaics (PV) to comply with Part L of the Building Regulations. With these regulations becoming more stringent in the next couple of years, it is possible that all new builds will need both heat pumps and PV just to be compliant.
For retrofits, the economic costs are more substantial. Including the airtightness measures, the ventilation system, and the heat pump, the cost is likely to exceed €15,000 (and that’s without further insulation measures). This cost would account for about 50 to 70 percent of the energy efficiency savings over a 20-year period. The 50 percent grant available under the Superhomes scheme means you should break even in about seven to 10 years.
- Up to 30 percent cheaper to run than a gas or oil boiler
- Much lower emissions than gas/oil boilers
- Low maintenance
- Lasts longer than conventional fossil fuel boiler
- Simple controls for adjusting temperature make them easy to use.
Whatever the short-term economic costs, you will be substantially better off from an environmental and comfort standpoint.
Solar heating systems can be used in conjunction with a heat pump for maximum energy efficiency and sustainability. They collect energy from the sun using solar collectors installed on the south-facing side of a roof and transfer it back into the house using an air or water network. Families can heat some 60 percent of their annual water requirements using solar systems.
PV versus Tube Systems
Flat plate PV panels are more durable, cost-effective, and low-maintenance than tube systems, and they look better too. The tube system works better with limited sunlight, however, so they are a good choice for cooler climates and roofs that are not south-facing.
New Builds versus Retrofitting
Solar heating is a more practical option when building a new home than it is for retrofitting an existing one. Unless there is other construction work taking place, it can be complex and expensive because it requires new plumbing. You will probably need to replace your existing hot water cylinder with a new solar compatible cylinder. These tend to be bigger than traditional hot water cylinders. You should also remember that, although solar systems provide up to 40 per cent of your hot water in winter, you will still need to use your boiler or immersion heater to raise the water temperature.
SEAI offers a grant of €1,200 for installing solar heating, €600 for updating your heating controls, and €700 for upgrading your boiler and heating controls.
To ensure the best performance from your heat pumps or solar system, it is vital that your home is well-insulated and relatively airtight. SEAI offers quite generous insulation grants to help you, and Superhomes also offers retrofit programmes to help you reach an A energy-efficiency standard.
Other sustainable heating systems worth considering include wood pellet or biomass boilers. These received a boost with the launch of Bord na Móna Bioenergy, a new division of Bord na Móna that aims to become Ireland’s key supplier of sustainable biomass. Until recently, the limited availability of biomass deterred people from installing wood pellet boilers
Heat Recovery Ventilation Systems (HRV Systems) are another energy-efficient heating option. The HRV System extracts heat from evaporated hot water in bathrooms and kitchens and then transfers this heat into fresh air ventilated into your home.
Ireland needs to take significant action to meet future targets for lowering greenhouse emissions, and your choice of home heating system can help. With the widespread availability of government grants, now is the perfect time to invest in a heat pump system, solar heating system, or alternative sustainable heating system as a dependable, efficient, low-carbon route to a cosy home.