Solar to Electric Hot Water: Is It Worth Upgrading?
Solar to Electric Hot Water: Is It Worth Switching?
Standard electric can be the simplest way to retire an ageing solar system — but it is usually a step backward in energy efficiency, so compare heat pump before you commit.
Solar hot water and standard electric storage both give you a tank of stored hot water, but they use very different energy pathways. Solar thermal captures heat from dedicated roof collectors and uses a booster when required. Standard electric removes the solar-thermal hardware and heats the tank with a resistance element. That can simplify the installation and future servicing, but it normally increases purchased electricity use compared with a healthy solar system or a suitable heat pump.
Should I Replace Solar With Electric?
This is a preliminary guide. Final suitability depends on the existing solar layout, tank position, electrical supply, roof work, household demand and whether a heat-pump site is available.
1What solar system do you have?
2Why are you considering replacement?
3What matters most for the replacement?
Guide only. Solar collector removal, roof penetrations, tank location, electrical circuit requirements, drainage, valves, household sizing and installation access must be assessed for the selected replacement.
Can You Replace Solar Hot Water With Electric Storage?
Yes. A solar hot-water system can be replaced with a conventional electric storage system where a suitable tank position and electrical supply are available. The conversion can be straightforward when the existing solar system already has a ground-level cylinder, but roof-mounted solar can require a completely new ground-level tank position and more plumbing or electrical work.
Why Do People Change From Solar Hot Water to Standard Electric?
The usual reasons are simplicity, lower replacement cost, difficult roof work or a desire to remove ageing solar-thermal equipment. Those are legitimate reasons, but they should be separated from energy efficiency because standard electric generally uses much more purchased electricity than a healthy solar system or a suitable heat pump.
Lower Upfront Purchase Cost
Conventional electric storage is usually cheaper to buy than a new solar-thermal or heat-pump system.
No Compressor or Fan
Electric resistance heating is virtually silent, which can matter in very tight sites near bedrooms or neighbours.
Remove Roof-Based Hot Water Hardware
The new system does not need solar-thermal collectors, circulation pipework or a roof-mounted hot-water tank.
Simpler Future Replacement
A conventional ground-level electric cylinder is a familiar, straightforward storage system for future servicing and replacement.
Collector Problems Can Be Retired
Ageing collectors, pumps, sensors, circulation lines or roof leaks can be removed from the new hot-water design.
But Energy Use Increases
The resistance element has to supply the heat that the solar collectors previously contributed, so simplicity comes with a running-energy trade-off.
Solar Hot Water vs Standard Electric vs Heat Pump
| Consideration | Existing Solar Hot Water | Standard Electric | Heat Pump |
|---|---|---|---|
| Main heat source | Direct solar thermal + booster | Resistance element | Heat from surrounding air + electricity |
| Upfront replacement cost | Keep if healthy | Usually lowest | Usually higher before eligible incentives |
| Energy use | Very low purchased energy when solar contribution is strong | Higher electrical demand | Strong advantage Around 30% of conventional electric hot-water energy use under Australian Government guidance |
| Roof equipment | Collectors / tubes and sometimes roof tank | No renewable collectors required | No solar-thermal collectors required |
| Solar PV compatibility | Separate technology using roof area | Can use daytime PV, but remains resistance heating | Best pairing Lower electrical demand makes daytime PV more effective |
| Noise | Usually very quiet | Very quiet | Compressor and fan operate while heating |
| STCs on new replacement | Eligible new solar systems may qualify | No renewable-hot-water STC pathway | Eligible listed heat pumps may qualify |
| Best reason to choose | System is healthy and still performing | Lowest upfront cost, silence or site constraints | Best long-term efficiency where the site suits |
Split Solar to Electric: Usually the Simplest Solar Conversion
A split solar system already has a ground-level cylinder. That usually gives the property an established tank footprint, hot and cold water services, drainage and often an electric booster circuit near the location where the replacement storage tank may go.
Existing Tank Position
The current ground-level site can often provide the starting point for a replacement electric cylinder if the base, clearances and dimensions suit.
Existing Plumbing
Hot and cold services can often be adapted rather than creating a completely new hot-water location.
Existing Booster Power
The solar booster circuit may be useful, but its cable, protection, control and capacity still need to be checked against the new electric element.
Roof-Mounted Solar to Electric: Expect More Conversion Work
Close-coupled solar can require more redesign because the old storage tank may be on the roof. Moving to standard electric usually means creating a new ground-level cylinder position and extending the services that were previously configured around the roof-mounted system.
New Ground-Level Tank Site
The electric cylinder needs a stable base, appropriate clearances, drainage and practical service access.
Pipework Changes
Hot and cold services may need to be rerouted or extended to the new cylinder position.
Electrical Circuit
Existing booster power may not terminate where the new ground-level tank will be installed, so circuit extension or new electrical work can be required.
Collector & Tank Removal
The roof-mounted tank, collectors or evacuated tubes and associated mounting hardware need to be dealt with appropriately.
Roof Penetrations
Redundant penetrations and mounting points need to be left weather-tight and suitable for the roof system.
Compare Heat Pump at the Same Time
If you are already creating a new ground-level tank site and electrical supply, the extra reasons for choosing standard electric over heat pump become much smaller unless noise or budget is the deciding constraint.
Already Have Solar PV? We Would Usually Choose Heat Pump Over Standard Electric
Solar thermal and solar PV are different. Once the thermal collectors are retired, your rooftop PV can power either a resistance-electric tank or a heat pump. The heat pump normally needs far less electricity to perform the same water-heating task.
Electric + Timer
A timer can shift resistance heating into the daytime solar window, which can reduce grid imports when enough PV is available.
Electric + Solar Diverter
A Catch Power-style diverter or similar control can feed surplus solar into the electric element, but it changes when the energy is used rather than improving the element's conversion efficiency.
Heat Pump + Solar PV
A heat pump uses much less electricity for the hot-water task, so the same PV system can cover more of the heating load and leave more generation available for the rest of the home.
If the heat-pump location works, we would generally recommend heat pump over standard electric even when electric is being controlled around solar PV. During cloudy weather, poor solar production or periods when other household loads are using the available PV, the lower electrical demand of the heat pump becomes even more valuable.
What Happens to the Existing Solar Collectors?
Once the solar-thermal system is retired, the roof equipment should be deliberately dealt with rather than treated as if it no longer matters. The exact scope depends on whether the array is flat-plate collectors, evacuated tubes or a close-coupled roof system.
Collector Removal
Removing redundant collectors or tubes can free roof area and prevent ageing hot-water hardware remaining on the roof indefinitely.
Roof-Mounted Tank Removal
Close-coupled systems may also have a full storage tank on the roof that must be safely removed when the system is retired.
Roof Penetrations & Mounts
Old pipe penetrations, brackets and fixing points should be left weather-tight and appropriate for the roof material.
Redundant Solar Pipework
Flow-and-return lines, pumps, controllers and sensors should be dealt with appropriately as part of the conversion scope.
Potential PV Roof Space
Retiring thermal collectors can create roof area that may be useful for future photovoltaic panels where the layout supports it.
Removal Cost Matters
Collector or roof-tank removal is separate from the replacement appliance itself and can materially affect the installed conversion cost.
Can the Existing Solar Booster Circuit Run the New Electric Tank?
Sometimes, particularly with a ground-level split-solar tank, but it should not be assumed. The existing circuit was designed for the old boost element and its control arrangement, not necessarily the new electric-storage element or preferred tariff setup.
Element Size
The new tank's element rating may differ from the old solar boost element, changing the circuit requirements.
Controlled Load
Some homes may choose off-peak or controlled-load operation, subject to retailer, distributor and electrical arrangements.
Solar Daytime Control
If rooftop PV is available, daytime scheduling may be considered instead of simply recreating the old booster timetable.
Protection & Isolation
Current electrical requirements and the selected tank determine the final protective devices and isolation arrangement.
Roof-System Wiring
A close-coupled solar system can have booster wiring routed to the roof, so a new ground-level tank may require extension or a different circuit path.
Heat-Pump Comparison
If electrical work is already required, compare whether the same project is better used to establish a heat-pump supply rather than locking in a larger resistance-heating load.
Do You Need the Same Tank Size as the Old Solar System?
Not automatically. Solar systems are often sized around collector contribution, booster operation and stored reserve. Standard electric recovery works differently, so tank capacity, element size, tariff window and household peak demand all need to be considered together.
Household Size
Occupants and daily hot-water demand determine the basic storage requirement.
Peak Shower Demand
Back-to-back showers, multiple bathrooms and baths can matter more than average daily litres.
Off-Peak Window
If the tank only heats during a controlled-load period, enough stored capacity is needed to carry the household through the rest of the day.
Element Recovery
Element size and available supply affect how quickly the tank can recover after heavy use.
Solar-PV Strategy
A daytime-controlled electric tank can be sized and scheduled differently from a traditional overnight off-peak setup.
Future Demand
Renovations, additional bathrooms or changing household size should be considered before selecting the smallest replacement.
What Happens to STCs and Rebates If You Switch to Standard Electric?
Conventional resistance-electric storage does not create renewable-hot-water STCs. Eligible new solar water heaters and eligible air-source heat pumps can participate in the federal Small-scale Renewable Energy Scheme when the exact model and installation meet current requirements.
No Renewable-Hot-Water STCs
A conventional resistance-electric tank does not have the same STC pathway available to eligible solar and heat-pump systems.
Eligible Models May Receive STCs
The exact heat pump must be on the current Clean Energy Regulator register and installed in its approved configuration within the eligibility period.
Extra Incentives Can Change the Gap
Some state or territory programs can further improve the economics of an eligible heat-pump replacement, so compare the complete eligible pathway before choosing electric solely from sticker price.
When Standard Electric Can Genuinely Be the Right Solar Replacement
There are situations where electric storage is the practical choice. We would choose it for a real site, noise or budget reason rather than treating it as the automatic replacement for an old solar system.
Lowest Upfront Cost Is Critical
For an urgent failure or tightly constrained budget, a conventional electric tank can be the most accessible replacement pathway.
Heat-Pump Noise Cannot Be Managed
A silent resistance-electric tank can be preferable where the only practical location is immediately beside bedrooms or a sensitive boundary and no reasonable alternate site exists.
Indoor or Enclosed Tank Location
A location that suits an electric cylinder may not provide the airflow required by a heat pump.
Very Low Hot-Water Demand
Low usage can reduce the absolute dollar value of the efficiency saving, making upfront cost more influential.
Simple Rental Replacement
Where the owner prioritises a straightforward low-capital replacement and energy use is modest, standard electric may be selected for simplicity.
Specific Electrical / Site Constraints
Every conversion is different. If a heat-pump relocation or site rebuild becomes disproportionate, electric can be the sensible fallback.
When Heat Pump Is the Stronger Replacement Than Standard Electric
If any of the conditions below apply, we would normally recommend comparing a heat pump before committing to resistance electric.
Split Solar Already Has an Outdoor Tank Site
The property already has a full-sized ground-level hot-water position. If airflow and noise separation are reasonable, that is an excellent starting point for a heat pump.
Rooftop Solar PV Exists
Heat pump can use daytime PV while requiring far less electrical energy than a resistance element for the same stored-hot-water task.
Running Cost Matters
If the household will stay in the property and uses meaningful amounts of hot water, lower electrical demand becomes increasingly valuable over time.
You Are Already Paying for Electrical Work
Once the job needs a new circuit or relocation, the incremental simplicity advantage of standard electric can shrink.
You Are Removing Solar Collectors Anyway
If the roof work is already happening, there is little reason to choose resistance heating purely because it avoids solar-thermal hardware.
Future Solar or Battery Is Planned
Reducing the hot-water electrical load preserves more solar generation and battery capacity for the rest of the house.
Current Electric & Heat Pump Starting Prices
Use collection pricing as the starting point only. Solar removal, roof work, electrical changes, tank relocation, valves, drainage and installation scope can materially change the final conversion cost.
The lower-upfront, silent replacement pathway where the property or budget favours conventional storage.
Current Installed Today collection starting price. Final installed cost depends on the selected system and conversion scope.
Higher initial purchase cost, but far lower electrical demand and possible STC or state-incentive pathways where eligible.
Current Installed Today collection starting price. Final value depends on model, location, eligibility and installation scope.
How a Solar-to-Electric Conversion Usually Works
The job starts with the existing solar layout. Split solar can be relatively direct; roof-mounted solar usually needs a new tank site. The redundant solar equipment then has to be properly retired as part of the project.
Identify the Solar Layout
Confirm tank location, collector type, booster, pipework, roof access and existing services.
Choose the New Tank Size & Site
Match household demand, tariff strategy and available footprint rather than simply copying the old solar tank litres.
Confirm Electrical Requirements
Check whether the old booster circuit can be reused, altered or needs a new route to the replacement tank.
Retire Solar & Commission
Remove or appropriately deal with redundant solar hardware, install the new tank, test operation and complete required compliance work.
Supply Only vs Supplied & Installed
Installed Today sells supply-only products across supported Australian metro areas and offers supplied-and-installed options where available in eligible Brisbane and Gold Coast service areas. Solar conversions can include roof work and electrical changes beyond a standard tank replacement.
You Arrange the Conversion
Arrange appropriately licensed trades to confirm the replacement tank, electrical supply, plumbing, collector or roof-tank removal, drainage and roof weatherproofing before installation.
- Product price is for the selected product unless the listing states otherwise.
- Solar removal and roof work are not automatically included.
- Confirm electrical and plumbing scope before ordering.
Available Where Supported
Where an Installed Today installation option is offered, check the included package and any additional solar removal, relocation, roof or electrical work required for the property.
- Installation availability is location dependent.
- Roof-mounted solar can require additional conversion work.
- Final site suitability remains subject to inspection and scope.
Solar to Electric Hot Water FAQs
Can I replace solar hot water with a standard electric tank?
Yes. Split solar can often use an existing ground-level tank site, while roof-mounted solar commonly needs a new ground-level cylinder position and additional plumbing or electrical work.
Is standard electric cheaper than replacing solar hot water?
A conventional electric tank is usually cheaper to buy than a new solar-thermal or heat-pump system, but the complete installed cost also depends on collector removal, roof work, electrical changes, tank location and plumbing.
Will electric hot water cost more to run than solar?
Usually, yes. A healthy solar-thermal system obtains much of its water-heating energy from the sun, while a standard electric tank relies on resistance heating whenever it reheats.
Should I replace working solar hot water with electric?
Generally not just for the sake of changing technology. If the existing solar system is healthy and performing well, continuing to use it can make more sense than replacing it early with a higher-energy-use system.
Is heat pump better than standard electric when replacing solar?
Where the site is suitable, we generally favour heat pump because it uses much less electricity than conventional electric storage. Standard electric has advantages in upfront cost, silence and some constrained locations.
What if I already have rooftop solar PV?
Both electric storage and heat pump can be scheduled to use daytime PV, but the heat pump needs far less electrical energy for the hot-water task. Where the site suits, we would normally choose heat pump over standard electric.
Can I use a solar timer or diverter with standard electric hot water?
Yes, suitable controls can shift or divert solar generation into an electric tank. That can improve solar self-consumption, but it does not change the underlying resistance-heating efficiency of the electric element.
Can the old solar booster circuit power the new electric tank?
Sometimes, but it must be checked against the new element rating, cable, protective devices, control method, isolation requirements and tank location. Roof-mounted solar can also require circuit extension to a new ground-level site.
What happens to the old solar collectors?
Redundant collectors, evacuated tubes, roof-mounted tanks, mounting hardware, pipework and roof penetrations should be deliberately addressed as part of the conversion scope rather than simply abandoned.
Does standard electric hot water receive STCs?
No renewable-hot-water STC pathway applies to a conventional resistance-electric storage replacement. Eligible new solar water heaters and eligible air-source heat pumps may qualify when the exact model and installation satisfy current scheme rules.
Do I need the same tank size as my old solar system?
Not automatically. The new electric tank should be sized around household demand, peak usage, element recovery, tariff window and any daytime-solar strategy rather than simply copying the old solar tank capacity.
Can I buy the replacement electric tank supply only?
Supply-only ordering is available on suitable products and delivery areas. Arrange appropriately licensed installers to confirm the solar removal, plumbing and electrical conversion requirements before installation.
Solar System Finished? Compare Electric — Then Check Heat Pump Before You Commit
If your old solar system is genuinely at the end of its life, standard electric can be the simple, quiet and lower-upfront replacement. But where the site can reasonably support a heat pump, we would compare heat pump before locking in resistance heating — particularly if rooftop solar PV is already on the home.
