Harnessing the sun

Heating water is usually the single biggest energy user in the home and, while other technologies in the house – such as lighting, refrigeration and heating – have become more efficient, it still takes the same amount of energy to heat a litre of water to 60°C. Rising costs of power mean that people are becoming increasingly motivated to do something to reduce the cost of running their homes while also personally tackling climate change, and using the sun to heat water is an easy place to start.

Marcus Baker, managing director at Apricus, explains: “A solar hot water system only needs 40W of electricity to run and provide your essential service of hot water. As it is simply capturing the sun’s energy directly as heat and transferring it to be stored in a hot water cylinder, the system is highly sustainable and can be a core resilience feature for homes, commercial buildings and dairy farms, in the face of a changing climate.”

Apricus has been operating in New Zealand since 2003 and the company’s sole offering is solar hot water systems, which means, as Marcus says, that they are experts on the subject. The company’s systems utilise high-quality, high-performance evacuated tube collector technology to capture solar energy and convert it to hot water.

As well as being suitable for use in the home, the systems are installed in commercial buildings and three projects that directly illustrate this resilience are referred to by Marcus. Two are fire stations in Hamilton and Christchurch, and the third is the new Manawatu-Whanganui Regional Council building, to be completed later this year in Palmerston North.

All three buildings are rated to Civil Defense Importance Level 4 (IL4), which means that, if a civil emergency were to occur, they need to continue to operate and be a place of refuge. The fact that Apricus’ systems only need a tiny amount of power to work means that in the case of an extreme event, the buildings will still have hot water, even if the mains grid is down.

The systems are not only practical in extreme conditions. At home, Apricus customers barely need any electricity to heat water in summer. During winter and on cloudy days, Marcus says that the system will still provide hot water. If the solar hasn’t heated up the cylinder sufficiently, the smart controller will automatically switch an electrical booster element on until the cylinder reaches 60 degrees. It then switches this off to minimise electricity use the next day.

As power prices across New Zealand continue to rise, cost reduction remains one of the main benefits of installing an Apricus solar hot water system. The systems can reduce energy consumption for hot water by three-quarters, equal to a third off the total of an average yearly power bill.

In addition to the cost-saving benefits, Marcus comments that the system is an entirely complementary technology to solar electric photovoltaic (PV) panels. “As the solar hot water panels only take up a small area of the roof, they can easily be fitted next to PV panels,” he says. “This means you can have two relatively affordable systems side by side for optimal benefit, and a smaller, affordable PV system can be used for the fridge, dishwasher and appliances on standby – not for hot water.”

As well as increasing discussion around the use of PV panels, there is a lot of talk about the environmental and cost benefits of installing a battery in the home. However, Marcus suggests that “every single house already has (or has an easy option to have) a fully-rechargeable, fully-recyclable, low-cost battery – the hot water cylinder. This can literally be transformed into a solar heated battery with an Apricus system.”

Once the house battery is taken care of with the Apricus solar hot water system and cylinder, then the best use of an electrical battery is in your car. “If you are looking to buy a battery for storing electrical energy, in terms of reducing costs and impact on the environment, it is much better to buy an electric vehicle than to install a battery in your home, as you will save three times the amount of money, while vastly reducing your carbon emissions.”

Apricus’ solar collector tubes work well in cold weather and the compact frames are highly durable, withstanding all wind zones and coastal conditions. All of Apricus’ systems have a 10-year warranty with local support from installers and have been rigorously tested in Europe and America to demanding standards.

We have an enviable number of sunshine hours in many parts of New Zealand so it makes sense to harness that solar energy in a sustainable way to heat water. And, with the ever-more pressing imperative to reduce our carbon emissions, solar hot water systems provide both environmental and cost-saving benefits, as well as increasing resilience within our communities and homes in case of the worst.

Find out more about Apricus' innovativesolar hot water systems here.