May 14, 2014
Solar Secrets of South-Facing Houses
To gain the maximum energy benefits from the sun, you need to live in a South-facing house.
While it is well known that the sun reaches its midday peak high in the Southern sky, you may not realise the significant renewable-energy differences that can be gained from having a South-facing house or roof.
Let’s take a look now at familiar domestic solar-energy technologies and designs, but with special emphasis on seeing how a South-facing house optimises their benefits.
Solar Photovoltaics and Solar Thermal
Solar Photovoltaics (also known as Solar PVs) is a technology that allows sunlight to be converted into electrical energy. This energy is used directly by a building, helping to both reduce energy costs, and to provide a clean energy source.
Solar Thermal panels use the sun’s energy to heat domestic water. Typically, they can provide around 50% of a home’s yearly hot water requirements.
For Solar PVs and Solar Thermal panels to be at their most effective, they need to have as much sunlight exposure as possible. This is best achieved by installing them on a South-facing roof with unrestricted exposure to the sky.
A solar panel facing directly South will operate at 100% of expectations. An East or West-facing panel will operate at around 80% of expectations. A North-facing panel will only operate at around 60% of expectations.
As the above figures show, in most cases, it is not cost efficient to have solar panels fitted in a North-facing orientation. East and West directions are acceptable. However, for the most favourable energy generation or water heating, you should have the panels fitted in a South-facing orientation.
The payback time for solar-energy installations is substantially reduced if you can fit the panels on an advantageous South-facing roof. Ideally, your roof should have a pitch of 45 degrees.
Passive Solar Houses
Imagine a house that does not need a heating system in cold weather.
You may think this sounds like pure fantasy, but it is not. They are already in existence, and are known as passive solar houses.
These houses are designed to capture direct sunlight through solar-orientated windows. The sunlight is converted into heat which in turn warms the interior of the building.
A passive solar house works best when sunlight is allowed to enter the building from 9am to 3pm. This is achieved by ensuring that the main windows of the house are South-facing. Normally, this involves orientating the house with its long axis perpendicular to True South.
As with solar panels, passive solar houses demonstrate the hidden power of a South-facing home.
Go Green, Go South
While you may not currently live in a South-facing house, hopefully this article will inspire you to consider one next time you move home. Remember, for solar panels it is not required for the house to face South, only that you have a South-facing roof available for them to be installed onto.
Think long-term.
If global energy prices continue to increase (as seems likely), then the solar benefits of a South-facing home will surely add value to these properties. With this in mind, it would also make sense for property developers to build as many of their homes in a South-facing direction.
You may of course simply want to have more of your domestic energy from a green source. South-facing homes will help you turn this dream into a reality.
*Please note this article is written for readers in the Northern hemisphere. If you are in the Southern hemisphere, then your optimum solar direction is North.
Craig J Todd – Freelance writer with a passion for tech, trends and simplicity.
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As I’m considering both of these things (which is why I did the Google search that led me to this article) I’m coming up against a conundrum: in order to have the greatest amount of south-facing roof surface, you have to give up a lot of south-facing wall and thus passive solar gain. I’m thinking about shed roofs in particular, which have the greatest roof surface area facing in one direction, and conversely offer the greatest potential for a large wall of windows facing one direction. But you can’t have both facing south! A conventional gable roof offers the best compromise, but to have enough solar panels on the south side you have to give up on south light inside under the roof. At best you waste a lot of space by having a tall roof perched on top of the living space.
I don’t suppose you’d be interested in researching innovative solutions people have found to this conundrum?
Hi Joy! Thank you for your comments and question. I would suggest contacting one of the major solar panel manufacturers such as http://www.solarcentury.com/uk/ and http://www.solarcity.com/ Given that solar is their expertise, I would expect them to be able to offer you some suitable advice. Good luck. Craig