Nov 2022

What is a Powerhaus, and why you need one

A PowerHaus is a house that can meet its own energy needs with standard household solar. This sounds simple, but it isn’t the norm.

We invented the term PowerHaus after seeing a huge gap in the building industry. The current Australian code doesn’t encourage people to adopt best practice, and many people don’t know how achievable it is to have a comfortable, low-bill home that uses mostly renewable energy.

Here are 3 reasons why most homes aren’t yet a PowerHaus:

  1. Australian building standards just aren’t that great. Yes, they’re moving in the right direction. But they’re not quite there yet.
  2. We Australians like huge houses. The bigger the house, the more energy you need to keep it at the right temperature. You also need more materials to build it, which uses more embodied carbon – see Canberra’s Low Carbon Challenge.
  3. We live in a highly technological age. This means screens and so many devices…all using more power.

Here’s why everyone should aim for a PowerHaus:

  1. No or minimal power bills. Yes, that’s right. We’re tracking ours (link to come!) and we’ve been living almost bill-free for a year.
  2. Make a positive contribution to solving climate change by not relying on fossil fuels.
  3. Create a comfortable home. It’s a wonderful feeling when you open the door after a cold, crispy day and enter a home that is balmy and full of good cheer.
  4. Have a safer home. We want healthy air in our homes. That means free from nasty mould that can trigger all sorts of illness. It also means that our home is a safer place during fires (because air is controlled and filtered) and floods (no follow-on mould issues from high humidity).

Three ways to make your home a powerhouse: orientation, systems and specifications.

The 3 main principles for PowerHaus success

  1. Use the sun’s energy for free passive heating with clever design, north-facing windows, and high-performance building details.

To understand passive heating in your house, you need to look at the design of your house and the temperature throughout the house. Why is temperature so important? Because heating and cooling make up almost 50{64b2618efa6fabeb730d2d737dd35683e06c117ce5874ebc6252000bb6a88278} of your energy needs – so if your house is comfortable without using electricity, you’ve pretty much halved your energy bill. Other big power guzzlers can include your hot water system, refrigerator, water pumps (for pools) and some larger TVs or monitors.

The first principle for success here is simple: the sun is your best source of free heat. In winter you want maximum sun coming into your house (we’re talking colder climates here… anywhere south of Sydney and Perth). In summer, you want minimum sun coming in.

“If your house is comfortable without using electricity, you’ve pretty much halved your energy bill.”

  1. Use energy efficient systems in your house.

The single most important thing to know about energy systems in your house is:

Use heat pumps!

Heat pumps could literally help save our planet. Why are they so amazing? Because they produce 3 times as much energy as they use. So, if you’re heating your house with a split system (a heat pump), it will produce 3kW of heat energy for every 1kW of energy used.

In comparison, any other radiant form of heat – such as in-slab heating or bar heaters – use 1kW energy to produce 1kW heat.

  1. Install solar and smart systems to use your free power

Powering your house with solar isn’t as simple as installing it. To be a PowerHaus, you need to use the energy you produce.

This means moving your energy consumption to the time of day when your solar is generating the most electricity (daylight hours). By doing this you’re also ensuring the grid is not overloaded with power fed through during the day, which is something grid managers are getting increasingly anxious about.

When you lower the amount of power you are sending back to the grid during the day, you won’t be hit with a feed-in tariff. You’ll be effectively saving anywhere between $0.20-35c/kWh when you use your freely-generated solar power – which can translate into thousands of dollars in savings on your winter energy bill.


Want to make your home a Powerhaus? Request a quote to find out how we can help.

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