Electric to Solar Hot Water: Is It Worth Upgrading?
Electric to Solar Hot Water: Is It Worth Switching?
Yes, where the roof genuinely suits solar thermal - but if the home already has strong rooftop PV or the solar roof is only marginal, a heat pump is usually the first alternative we would compare.
Moving from conventional electric storage to solar hot water can reduce the amount of purchased electricity used for water heating by capturing heat directly from the sun. The conversion can keep a ground-level storage tank with split solar or move the tank and collectors onto the roof with a close-coupled system. Roof exposure, collector position, booster use, access and installation cost all matter.
Does Solar Suit Your Electric Replacement?
This is a preliminary guide. Final suitability depends on roof exposure, collector layout, structure and access, tank position, booster requirements, electrical supply and household demand.
1What is the roof like?
2Do you already have rooftop solar PV?
3What matters most?
Guide only. Solar collector orientation, shading, roof condition, structural requirements, safe access, tank configuration, booster requirements and household hot-water demand must be checked before finalising a conversion.
Can You Replace Electric Storage With Solar Hot Water?
Yes. Standard electric storage can be replaced with either split solar hot water, which keeps a storage cylinder at ground level and adds roof collectors, or close-coupled solar, which places the tank and collectors together on the roof. The existing electric tank position can be a useful starting point for a split-solar conversion.
Electric vs Solar vs Heat Pump: What Actually Changes?
All three can provide stored hot water, but they use electricity and solar energy very differently.
| Consideration | Standard Electric | Solar Hot Water | Heat Pump |
|---|---|---|---|
| Main heat source | Resistance element | Direct solar thermal + booster | Heat from surrounding air + electricity |
| Roof equipment | None | Dedicated collectors or evacuated tubes | None required for thermal collection |
| Solar PV compatibility | Can be timer or diverter controlled | Uses separate thermal collectors | Strong advantage Can use household PV electricity |
| Operating noise | Very quiet | Usually quiet; some split systems use circulation equipment | Compressor and fan operate while heating |
| Roof dependency | Low | High | Low |
| STCs | No renewable-hot-water STC pathway | Eligible listed systems may qualify | Eligible listed systems may qualify |
| Best fit | Lowest upfront simplicity or difficult renewable site | Excellent sunny roof and direct solar thermal preference | Efficient upgrade where PV exists or roof space is limited |
Why Move From Standard Electric to Solar Hot Water?
The main attraction is reducing how often a resistance element has to supply the full water-heating load from purchased electricity.
Use Direct Solar Heat
Collectors capture solar energy specifically for water heating, reducing reliance on the booster when solar conditions are strong.
Reduce Resistance Heating
Conventional electric storage relies on an element whenever heating is required. Solar can shift a large share of that task to the sun.
Potential STCs
Eligible listed solar water-heater systems can create Small-scale Technology Certificates when installed in the approved configuration.
Keep Stored Hot Water
The household retains a stored reserve rather than changing to a continuous-flow delivery style.
Quiet Renewable Option
Solar thermal avoids the compressor and large fan used by heat-pump systems, which can matter in noise-sensitive locations.
Roof-Based Energy Collection
Homes with an excellent unused solar roof can dedicate part of that area specifically to water heating.
Already Have Solar PV? Heat Pump Becomes the Stronger Comparison
Solar thermal and solar PV are different technologies. If the roof already has useful PV capacity, a heat pump can use that electricity efficiently without adding a second solar platform dedicated only to hot water.
Electric + Timer / Diverter
Daytime control can increase solar self-consumption, but the resistance element still needs far more electrical energy than a heat pump for the same heating task.
Solar Thermal
Dedicated collectors directly heat the water but use their own roof area and add roof-specific installation and servicing requirements.
Heat Pump + PV
A heat pump can operate during solar-production hours and use far less electricity than a conventional resistance element, leaving more PV available for the rest of the home.
If you already have strong rooftop PV and the heat-pump site is workable, we would usually compare heat pump before adding solar thermal. A timer or Catch Power-style diverter can improve a standard electric system, but it changes when the resistance element runs rather than removing its higher energy demand.
When Solar Hot Water Is the Stronger Upgrade
Solar deserves the strongest recommendation when the property itself gives solar thermal a clear advantage.
Excellent Sunny Roof
Strong, unshaded collector exposure is the foundation of a good solar-hot-water installation.
You Specifically Want Direct Solar Thermal
If the goal is to heat water directly from the sun rather than use a refrigeration cycle, solar is the obvious renewable pathway.
Quiet Operation Matters
Solar avoids a heat-pump compressor and large fan, which can be important near bedrooms or close boundaries.
Roof Access Is Straightforward
Good access lowers installation complexity and makes future collector servicing more manageable.
You Want to Free Ground Space
A suitable close-coupled system can place both tank and collectors on the roof, subject to structure and loading.
Booster Use Should Be Low
Good solar exposure, correct collector area and proper tank sizing help minimise reliance on electric boosting.
When We Would Recommend Heat Pump Instead
If the solar case is only marginal, heat pump usually becomes the stronger long-term upgrade from standard electric.
Rooftop PV Already Exists
The home already has a solar-electric platform that can power efficient water heating during the day.
Roof Is Shaded or Crowded
Heat pump does not depend on dedicated sunny collector area in the way solar thermal does.
Roof Access Is Difficult
Keeping the main hot-water hardware at ground level avoids collector installation and servicing on a difficult roof.
The Existing Tank Site Is Good
An outdoor electric-storage position can often be a very practical heat-pump site if airflow, noise and drainage suit.
You Want Simpler Future Servicing
Heat-pump components are usually accessible from ground level rather than spread between tank and roof collectors.
The Choice Is Close
Where both technologies are technically possible but solar has no clear roof or noise advantage, we would usually favour heat pump.
Split Solar or Close-Coupled Solar After Electric Storage?
Because the home already has a ground-level electric cylinder, split solar is often the more natural physical conversion. Close-coupled solar can instead move the entire stored-water system onto the roof.
Ground-Level Tank + Roof Collectors
The new solar cylinder remains at ground level and connects to roof collectors through dedicated solar pipework.
- Existing electric-tank position may be reusable.
- Hot and cold services are already nearby.
- New collector pipework is required to the roof.
- An electric or gas booster may be required depending on the system.
Tank + Collectors on the Roof
This places both the solar storage tank and collectors on the roof, freeing the old electric tank position at ground level.
- Roof structure and loading become more important.
- Safe installation and future access matter.
- Ground-level space can be reclaimed.
- Existing plumbing may need more substantial alteration.
Can the Existing Electric Tank Position Be Reused?
Often potentially yes for split solar. The old electric site already has a storage footprint, hot and cold water services, electrical supply and usually drainage nearby, but the new solar cylinder may have different dimensions and connection requirements.
Base & Footprint
The existing slab or support needs to suit the new solar cylinder's size and loaded weight.
Hot & Cold Plumbing
Existing services can often be adapted, although connection positions may differ.
Drainage
Relief-valve drainage must suit the new system, and collector-system requirements also need to be considered.
Collector Pipe Route
Split solar needs a practical route between the ground-level tank and roof collectors.
Electrical Booster
The existing electric supply can be useful, but the booster circuit and control arrangement still need to suit the selected solar system.
Heat Pump Alternative
The same ground-level site may also suit a heat pump, which can avoid roof collectors entirely.
What Happens When There Is Not Enough Sun?
Solar hot water still needs backup heating for poor weather, winter conditions, unusually high demand or periods when collectors cannot provide enough useful heat.
Electric Boosting
An electric element can bring the stored water to the required temperature when solar contribution is insufficient.
Gas Boosting
Some systems can use gas backup, although this adds gas infrastructure and ongoing fuel dependency.
Sizing Matters
Collector area, tank capacity, household demand and local solar conditions influence how often boosting is needed.
Can Electric-to-Solar Replacement Qualify for STCs?
Yes, potentially. The federal Small-scale Renewable Energy Scheme includes eligible solar water heaters and eligible air-source heat pumps. The new solar system must be a listed model and installed in its approved configuration within the eligibility period.
Eligible Systems Can Receive STCs
The exact collector, tank and approved system configuration must match the current Clean Energy Regulator listing and installation rules.
Standard Electric Does Not Create Hot-Water STCs
The renewable-hot-water certificate pathway applies to eligible technologies such as listed solar water heaters and air-source heat pumps, not conventional resistance-electric storage.
Confirm the Claim Pathway Before Installation
Product eligibility alone does not complete an STC or state incentive claim. Confirm the installer, registered agent and any pre-approval requirements first.
Current Electric Starting Price vs a Solar Conversion
Standard electric storage can be the cheapest product to replace upfront, but solar adds dedicated collectors, mounting and roof work in exchange for much lower reliance on resistance heating. Compare the complete installed scope rather than tank price alone.
Usually the simplest and lowest-upfront replacement where the existing site and electrical supply remain suitable.
Current Installed Today electric collection starting price. Final installed cost depends on size, location and installation scope.
Best where roof exposure is excellent and the homeowner genuinely wants direct solar thermal rather than simply a cheaper-to-run replacement.
Allow for collectors, mounting, roof access, solar pipework, booster requirements and any changes to the existing tank position or services.
How an Electric-to-Solar Conversion Usually Works
The exact scope depends on whether split or close-coupled solar is chosen. Start with the roof, then determine how much of the existing electric-storage site and services can be reused.
Assess the Roof
Check solar exposure, shading, collector area, roof material, pitch, structure and safe access.
Choose Split or Roof-Mounted Solar
Decide whether to retain a ground-level tank position or move the full system onto the roof.
Confirm Booster & Services
Check electrical or gas boosting, plumbing routes, drainage and any required service changes.
Remove Electric Tank & Commission Solar
Remove the old electric system, install the solar tank and collectors, complete the booster connection and commission the new system.
Supply Only vs Supplied & Installed
Installed Today sells hot-water products online with supply-only ordering across supported Australian metro areas and supplied-and-installed options where available in eligible Brisbane and Gold Coast service areas. Solar conversions can involve roof work and system-specific installation requirements beyond a standard electric replacement.
Confirm the Full Solar Layout First
Arrange appropriately licensed trades to confirm collector position, tank layout, booster, plumbing, roof work and incentive pathway before purchasing the system.
Availability Depends on Product & Location
Where an Installed Today installation option is offered, review the product's installation inclusions and any additional roof, relocation, electrical or plumbing work required for the property.
Electric to Solar Hot Water FAQs
Can I replace electric storage with solar hot water?
Yes. Standard electric storage can be replaced with split or close-coupled solar hot water where the roof, tank position, services, booster and installation conditions suit the selected system.
Is solar hot water better than electric storage?
Solar can substantially reduce reliance on resistance-electric boosting when the roof has strong solar exposure and the system is correctly sized. Standard electric is usually simpler and cheaper upfront but uses more purchased electricity for normal water heating.
Should I choose solar or a heat pump?
Solar is strongest on an excellent sunny roof when direct solar thermal or quieter operation is specifically wanted. Heat pump is usually stronger where rooftop PV already exists, roof space is limited, the roof is shaded or easier ground-level servicing is preferred.
Can I reuse the existing electric tank position?
Potentially with split solar. The base, footprint, plumbing, drainage and booster arrangement still need to suit the selected solar cylinder.
Does solar hot water still need electricity?
Many solar hot-water systems use an electric booster and some split systems also use circulation equipment. The amount of booster use depends on solar contribution, household demand and system design.
What if I already have rooftop solar PV?
Existing PV strengthens the heat-pump comparison because a heat pump can use household-generated electricity without adding a separate solar-thermal collector array. Solar thermal can still make sense if roof area remains excellent and direct solar heating is specifically preferred.
Can I keep electric storage and add a solar timer or diverter instead?
Yes, where the electrical and solar setup suits. A timer or diverter can increase use of daytime PV, but it does not change the resistance element's underlying energy requirement. A suitable heat pump can use substantially less electricity for the same water-heating task.
Can electric-to-solar replacement qualify for STCs?
Eligible listed solar water-heater systems can create STCs when installed in the approved configuration within the model's eligibility period and all scheme requirements are met.
Should I choose split solar or close-coupled solar?
Split solar is often the more natural conversion from electric storage because the home already has a ground-level tank site. Close-coupled solar can free ground space but places the tank and collectors on the roof.
When would you recommend heat pump instead of solar?
Heat pump is usually the stronger first comparison when rooftop PV already exists, collector exposure is only average, roof space or access is limited, or the existing outdoor electric-tank site is already well suited to a heat pump.
Replacing Electric Hot Water? Compare the Roof Before Choosing Solar
Electric-to-solar can be an excellent upgrade where the roof is genuinely strong and direct solar thermal is the goal. If rooftop PV already exists or the roof is only marginal for thermal collectors, compare a heat pump before committing - it may deliver the stronger overall pathway with less roof-specific infrastructure.
