Thinking about switching to solar hot water? You’re not alone. More and more Australians are turning to solar systems as a way to save money on energy bills and reduce their environmental impact.
But with several types of solar hot water systems available, choosing the right one can feel overwhelming. Each system works a little differently and suits different homes, climates and budgets.
That’s why it’s important to understand how they operate before making a decision. In this blog, we’ll break down the three main types of solar hot water systems – thermosiphon, split systems, and heat pump systems.
We’ll explain how each one works, their pros and cons, and which situations they’re best suited for. Let’s take the guesswork out of going solar and help you find the perfect system for your home.
1. Thermosiphon Systems
Thermosiphon systems are one of the most popular and straightforward types of solar hot water setups. They use natural convection to move water – meaning no pump is required, which helps reduce maintenance and energy costs.
Here’s what you need to know:
- Roof-mounted design: The storage tank and solar collectors are both installed on the roof. Hot water rises naturally into the tank as it’s heated by the sun.
- No moving parts: With no pump involved, there are fewer components to maintain or replace.
- Cost-effective: Installation is generally cheaper than more complex systems, and ongoing running costs are low.
- Best for warm climates: They perform well in sunny areas but may struggle in colder regions where heat loss can be greater.
- Simple operation: Great for homeowners looking for a low-maintenance, reliable setup.
- Space-saving: Ideal for homes with limited space on the ground but sufficient room and structural support on the roof.
- Less flexible in design: Because the tank must be above the collectors, it limits where the system can be installed.
If your roof can support the weight and you live in a warm climate, a thermosiphon system could be a smart, efficient choice.
2. Split Systems (Pump-Circulated)
Split systems, also known as pump-circulated or active solar hot water systems, offer more flexibility than thermosiphon systems. They separate the storage tank from the solar collectors, making them ideal for modern homes with design or structural limitations.
Here’s how they work and why they might suit your home:
- Tank on the ground: The storage tank is installed at ground level or indoors, while the solar collectors remain on the roof.
- Pump-assisted circulation: An electric pump moves water between the tank and the panels, ensuring efficient heating even when the tank is not above the collectors.
- Flexible design: Ideal for multi-storey homes or roofs that can’t support a heavy tank.
- Cleaner aesthetic: With no bulky tank on the roof, your home maintains a sleek look.
- Efficient in various climates: Performs well even in cooler or cloudy areas with the help of a booster.
- Higher installation cost: Slightly more complex setup and additional components like the pump can increase upfront costs.
- Requires electricity: While it is a solar-powered system overall, it still needs power for the pump.
If you’re after design flexibility and strong performance year-round, a split system is well worth considering.
3. Heat Pump Solar Hot Water Systems
Heat pump solar hot water systems work a bit differently from traditional solar panel systems. Instead of using direct sunlight, they extract heat from the air – similar to how a reverse-cycle air conditioner works.
This makes them a great choice for cooler climates or shaded homes. Here’s what you should know:
- No roof panels required: Heat pumps don’t rely on solar collectors, so they’re ideal if your roof has limited sun exposure or space.
- Works in all weather: Even on cloudy or cold days, the system can still heat water efficiently using ambient air.
- Energy-efficient: Uses a small amount of electricity to run the compressor but still consumes far less energy than a standard electric water heater.
- Easy to install: Installation is often simpler than systems with roof panels – everything stays on the ground.
- Government rebates available: In many regions, rebates or incentives help offset the upfront cost.
- Best suited for temperate climates: They perform best in areas where the ambient temperature doesn’t drop below freezing too often.
- Quiet and compact: Most units are relatively quiet and don’t take up much space.
If you want a low-energy, all-weather option that doesn’t rely on full sun, a heat pump system is a smart choice.
Choosing the Right Solar Hot Water System
Selecting the right solar hot water system comes down to understanding your home’s needs and the climate you live in.
For starters, think about your roof space. If your roof can handle the weight of a tank, a thermosiphon system might be ideal – it’s simple and doesn’t rely on pumps. However, if you want the tank on the ground for aesthetic or structural reasons, a split system with a roof-mounted panel and ground-level tank could suit you better.
If you live in a cooler area or your roof doesn’t get much sun, a heat pump system might be the smartest choice. These units don’t rely on direct sunlight and instead draw warmth from the surrounding air, making them perfect for shaded or chilly environments.
You’ll also want to factor in your household size, hot water usage, budget and any government rebates available. Larger families might benefit from bigger tanks or systems with boosters for cloudy days.
Finally, always consult with a professional installer – they can assess your home and recommend the most efficient and cost-effective option. With the right system in place, you’ll enjoy reliable hot water while lowering your energy bills and environmental footprint.
Consider Your Personal Needs
When it comes to solar hot water systems, there’s no one-size-fits-all solution. The best choice depends on your home, climate and personal preferences.
Thermosiphon systems are great for simplicity and sunny climates. Split systems offer flexibility and sleek design for modern homes. Heat pump systems, meanwhile, are perfect if your roof isn’t ideal for solar panels or if you live in a cooler area.
Each option helps reduce energy costs and environmental impact, so whichever you choose, you’re making a smart move. Still unsure? A licensed installer can assess your home and help match you with the right system.
With the right setup, you’ll enjoy reliable hot water and long-term savings – all while doing your part for a greener future. It’s a win-win for your wallet and the planet.
Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.
FAQs About Solar Hot Water Systems
Do you have any questions about solar hot water systems? If so, we’ve got answers to the most commonly asked questions below.
Yes, they do. While solar hot water systems are most efficient on sunny days, many come with a backup booster – either electric or gas – to ensure you still have hot water when the sun isn’t shining. Heat pump systems also work well in cloudy weather because they draw warmth from the air rather than relying on direct sunlight.
You can save quite a bit over time. Depending on your household size and local energy rates, solar hot water systems can cut your water heating bills by 50-80%. The initial investment may be higher, but the long-term savings and available rebates often make it well worth it.
With proper maintenance, a quality solar hot water system can last 10 to 20 years or more. Regular servicing, such as checking for leaks, cleaning panels, and inspecting valves, helps extend its life and ensures it runs efficiently year-round.
