Using the sun
In New Zealand, solar radiation is an abundant energy source.
Good house design that makes the most of solar energy can result in significantly lower heating costs in winter. Similarly, good design can reduce the need for cooling in summer.
On this page:
Design tips for using the sun
When planning for either renovation or building a new home, consider your home’s layout in relation to the sun, that is, work out which rooms need sun and when.
Ideally, your home should face north. There is a range of directions around true north that can be considered ‘north’: from 20 degrees west to 30 degrees east of true north.
Also consider the sun’s different positions in summer and winter and through the day. (See Fig. 1.)
Fig. 1 Paths of the sun |
Take action
Plan your design
When planning your home, consider how you can use the sun’s energy for heating and hot water requirements.
Checklist about using the sun
Use this checklist when planning your building design:
1. Insulation
To get the most from the sun, aim to keep its free heat in your home for as long as possible. Insulating your ceiling, floors and walls will help slow heat loss. Find out more about how to plan for insulating your home in the section on Insulation.
2. Use thermal mass
The best way to store the sun’s heat is to use thermal mass. An internal concrete floor will soak up heat from direct sunlight then release it as the temperature drops. Learn more about using thermal mass in the section on Concrete floors.
3. Install solar water heating
Most parts of New Zealand have enough sunlight to make solar water heating worthwhile.
Depending on the time of year and where you live, standard solar water heating systems can contribute a significant amount of your household’s water heating needs. This can be up to:
- 75% in summer
- 25-45% in winter.
Consider solar hot water heating
You will make significant savings to your power bill by installing a solar hot-water system when you build. Find out how solar hot water heating can work for you at Solar water heating. [ECCA website.]
More information:
Design
- Passive design for energy efficiency [Consumer Build website.]
- Design for the sun – Vol 1 [PDF 6MB]
- Design for the sun – Vol 2 (this can be ordered on CD from EECA. Please call 0800 358 676 for a copy.)
Passive heating
- Positioning for the sun [Smarter Homes website.]
- Passive heating [Smarter Homes website.]
Solar energy
- Passive solar designs for New Zealand homes (PDF 329KB) [ECCA website.]
Thermal mass
- Using thermal mass for heating and cooling. [Smarter Homes website.]