New Build

The financial and environmental benefits of renewable energy systems are well understood, and if you’re combining these in the build of a new house you have the perfect opportunity both to design the building to take maximum advantage of the cost-saving properties of these technologies and to go back to first principles and apply the ‘energy hierarchy’ to its full extent.

When planning a new home, a conscientious designer will consider these factors:

  • How do I make the building fabric more energy efficient?
  • How do I design the building to maximise efficiency of use?
  • How do I provide energy in a cost effective way with least impact on the environment?

Modern building materials mean new houses can be extremely well insulated, which minimises energy loss, but how about the potential for energy gain? For example, designing small windows into north-facing walls and large windows into south-facing walls will introduce considerable free solar energy into the building, and in some modern dwellings is the only source of energy required for space heating.

Large windows create more natural light, which minimises dependency on electricity to power artificial lights; smaller living spaces have fewer drafts and are cheaper to heat; designing kitchen and bathrooms close to the hot water source means less heat loss through long pipe runs.                                            

All these principles are fundamental, but at Solarsense we often find new houses have been designed with renewable energy options added almost as an afterthought, failing to get the maximum from these technologies. There are many enduring benefits to examining the project – with renewable energy options – holistically.

And don’t forget the generous financial incentives currently offered by the government for offsetting fossil fuels and reducing carbon emissions. The Feed-in Tariff is paid on all the electricity generated from solar PV; this electricity is available free to the householder and surplus can be sold to the National Grid. The government have also introduced the Renewable Heat Incentive (RHI), which pays an annual sum according to the quantity of fossil fuel offset by renewable heat technologies.

Here are some points that should be taken into account before you even start sketching your energy efficient home:

  • Solar PV attracts the Feed-in Tariff; RHI payments will be made on solar thermal systems
  • These technologies are most efficient when roof-mounted but can be ground mounted
  • A roof facing south of southeast and southwest is ideal, with a pitch of 25°-40°
  • Fewer gables, chimneys and vents means more available space and less shading
  • Be aware of shading from nearby trees and buildings
  • A typical 4kW PV system covers 28.5m2; 30 solar thermal tubes are 2.25m wide x 2.2m high
  • Consider cable routes for PV; solar thermal should be installed near the hot water cylinder
  • Roof-integrated systems are less obtrusive than conventional panels and save on roofing materials
  • Discreet solar slates and tiles are available
  • Modular PV/thermal systems are available that will form complete roofs
  • Some power saving devices for solar PV require an immersion heater
  • Batteries for PV systems need significant, frost free storage space
  • A solar thermal system will provide most of the household’s hot water needs May through September
  • Will attract an annual payment from the Renewable Heat Incentive (RHI)
  • A heat pump will save 40% over the running cost of a conventional oil-fired boiler
  • Will mean your home is not dependent on expensive fossil fuels
  • A heat pump is environmentally friendly
  • A very large area of land is required for ground source heating
  • An open loop heat pump can provide potable water from the borehole
  • Heat pumps for larger houses generally require 3-phase electricity
  • Heat pumps are not as quiet as conventional boilers so are best installed in a plant room
  • The heating circuit operates at a lower temperature and work best with larger radiators
  • Ground floor underfloor heating is ideal for heat pumps
  • Combining a solar thermal system will reduce summer use of the heat pump to almost zero

There are many permutations to the above systems and many more benefits than it is possible to list here. We would suggest that before you begin designing your home you call your nearest Solarsense office and we will be happy to arrange for a consultant to meet you and give full guidance on the best installations for your project.