How Much Can a Solar Hot Water System Save?

By heating the water directly from the sun, you rely very little on the electricity grid for your water heating needs. Solar hot water can reduce your water heating costs by 15-40%. Households or businesses that use considerable amounts of hot water can expect to save the most by installing solar hot water.

What are the Different Types of Solar Hot Water Systems?

There are 2 types of collectors you can choose from:

Flat Panel and Evacuated Tube Collectors

Flat panel solar collectors

Flat panel solar hot water collectors are ideal for those on a budget and in areas that are not affected by frost. These systems work on copper pipes running through a glass covered collector, sometimes connected to a water storage tank on the roof, though usually the storage tank is on the ground. The sun heats the copper pipes and the resulting hot water is fed back to the storage tank.

Evacuated tube solar collectors

This type of solar hot water system is higher efficiency and better suited to frost-prone areas, as they don’t crack when the temperature drops below freezing.

Evacuated tube systems can extract the heat out of the air on a humid day and don’t need direct sunlight. The total efficiency is higher and they perform better than flat panel systems when the sun is not directly on the collectors. eg. early in the morning or in the late afternoon. As well as being more efficient, they’re also more durable and cheaper to repair.

Evacuated tube solar hot water systems consists of two glass tubes that are fused at the top and bottom. The space between the two tubes is evacuated to form a vacuum. A copper pipe running through the centre of the tube meets a common manifold that is then connected to a slow flow circulation pump that pumps water to a storage tank below. This heats the water during the day. Because the tank is so well insulated, the water stays hot for a number of days.

With both types of systems, the sun generally provides sufficient heat to give you plenty of hot water for most of the year, but when there are a number of cold days, your system will need a helping hand (most likely in winter).  This is where your electric or gas booster comes in. This heats the water when there’s not quite enough heat in the sun to do the job.

How Hot Can Solar Hot Water Get?

In NSW, the regulation for water temperature in all bathrooms is 50ºC. Your actual tank temperature setting at the thermostat must be set at a minimum of 60ºC (to prevent bacteria and diseases from growing). A tempering valve is usually installed on hot water systems, which mixes your hot and cold water to deliver hot water at the tap at a constant and regulated temperature.

How Does Solar Hot Water Work in Winter?

Unlike solar power systems which work on light, solar hot water systems work on heat. This means that in the depths of winter, you may need to rely on your electric or gas booster to heat the water to your desired temperature. You’ll find the rest of the year, your solar hot water system will run straight from the sun.

Does Solar Hot Water Work on Cloudy Days?

Yes – though on cloudy days, your hot water system may need a boost. The booster will come on when the temperature of water in the storage tank falls below the thermostat setting and turn off automatically when the water reaches the required temperature.

What Solar Hot Water System to Buy

The type of solar hot water system you buy depends on whether or not you live in a frost prone area, what your budget is and how long a warranty you want.

For those on a budget, not in a frost prone area and who are happy with the standard warranty, we’d definitely suggest a flat panel system. The brands that we’re comfortable recommending are EnviroSun (previously known as Conergy), Chromagen and Dux.

For people who live in a frost-prone area, we’d only recommend an evacuated tube system. The best brands on the market are Apricus, SolarArk and Rinnai.

Apricus and SolarArk come with the longest warranties.

Like with anything you buy, you get what you pay for.

Can I Divert Some of My Solar Energy to My Hot Water System?

If you have a solar power system that’s producing more electricity than you’re using during the day, you might want to consider a CATCH Power solar energy diverter. With this clever device, you can divert some or all of the surplus solar energy that your system is sending to the grid to your hot water system instead. Fully installed, it’s only $1,700 (plus any travel costs): a lot cheaper than a supplementary solar power system at $4000 or battery storage at $11,000!

This makes a lot of sense, as you’re fully utilising the solar energy from your solar power system and it’s a low-cost investment. Get in touch if you’d like us to install a CATCH Power unit for you.

What If I Don’t Use a Lot of Hot Water?

If you don’t use a lot of hot water and you want a more environmentally friendly water heater, you may choose to get a heat pump water heater.

A heat pump water heater uses about 75% less energy to heat your water than a conventional electric hot water system.

A heat pump is an efficient type of storage water heater that extracts heat from the air. They are particularly useful if you have limited roof space for collectors/panels, have poor orientation or shading.

Be mindful that heat pumps make a low humming sound similar to an air conditioner so you won’t want to position your heat pump right next to a bedroom.

Heat Pump Water Heater

Is There Still a Rebate for Solar Hot Water in NSW?

Yes – there’s still a government rebate available.  The more efficient your system, the higher the government rebate. For most solar hot water systems, the RECs/STCs (government rebate) is around $1100. For most heat pumps, the rebate is worth about $950.

How Much Do Solar Hot Water Systems Cost?

This depends on the size and type of solar hot water system that you buy. We can help you choose the most effective solar hot water system for your requirements. Just get in touch and ask for a quote.

Your usage System size System price (after rebate)
Small user 170L heat pump $1,900
Medium user Either 280L heat pump;


Solar hot water with 2 collectors and a 315L tank




Large user Solar hot water with 3 collectors and a 400L tank $3,800

These prices are indicative. Additional costs such as tilt frames, power point installation, concrete slab provision, additional pipework, pipe size upgrades and gas to electric circuitry may apply.

Who Should I Choose To Install My System?

Just as important as the quality of the components you choose is the quality of the installation, as many corners can be cut by unscrupulous installers.

We recommend having your solar hot water or heat pump system installed by a company that’s been installing systems for at least 5 years and consistently receives good (independent) reviews on solar hot water comparison websites.

Solar Hot Water Quotes

The Energy Experts fast-track the quoting process for you by sourcing multiple competitive quotes on your behalf from local, professional solar hot water installation companies.

We’ve cherry picked solar hot water installers in your area that have a reputation for excellence and who are very competitively priced. Get a quote on a flat panel or evacuated tube solar hot water system or a heat pump system today.


Contact The Energy Experts on 1300 516 474 to receive a free quote/initial consultation about solar hot water, heat pumps, solar panels, battery storage or solar pool heating for your home or business.

Although our home base is in the Illawarra, we have reputable and experienced installers across the state, from the NSW South Coast (Tura Beach; Narooma; Ulladulla) to the Shoalhaven (Nowra), Southern Highlands (Bowral), Sutherland Shire (Greenhills Beach), Sydney (Gladesville; Auburn; Minto; Smeaton Grange), the ACT (Canberra), the Central Coast (Tuggerah), Newcastle (Warabrook) and the North West Slopes (Moree), New England (Glen Innes), the Blue Mountains (Katoomba) and the Central Tablelands (Oberon) regions.