Solar-Electric Hot Water Outperforms Heat Pump Hot Water

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Our Solar-Electric Hot Water Outshines, Outperforms, Outlasts, Outsilences
Feature	OneEnergy Sol•FlareSolar-electric hot water	Water Heat pumpHot water
Primary energy source	Free sunlight Solar panels power the cylinder element directly, with no battery or inverter. Sol•Flare adjusts continuously to use whatever the panels produce (10 W to 3,600 W). Mains power is only a backup top-up after low-sun days.	Mains power The compressor and fan run on mains electricity every heating cycle, day or night, all year, and the backup element draws more mains power in cold weather.
Lifespan	25+ years Solar panels carry 25-year manufacturer's warranties. Standard low cost electric cylinders have a 12–15 year lifespan, and the Sol•Flare controller has a design life of 20 years.	7–12 years Compressor wear limit life span to 7 - 12 years. Coastal salt air and cold-climate defrost cycles shorten life considerably and as much as 50%.
Lifespan savings	Exceptional	Average
Manufactured	German Designed & Manufactured SolFlare is robust German technology designed to last, manufactured in Austria, Europe.	Chinese Manufactured 95% of all heat pump hot water systems are manufactured in China.
Mains power avoidance	Up to 95% By consuming all available solar production, up to 95% of mains power is avoided, depending on array size, location and household use. Any short-fall during low-sun rainy days is topped-up by mains.	up to 65% At an ambient air temperature of 25°C, a heat pump avoids 50–65% of the mains energy traditionally used to heat water.
Moving parts, wear & tear, noise	Zero moving parts, silent Solar panels are static and the Sol•Flare controller is solid-state, with no moving parts to wear out or make noise. The standard low cost electric cylinder can be located anywhere, inside or outside, without disturbing anyone.	Compressor, fan, expansion valve, constant hum The sealed refrigeration system includes a compressor, condenser, expansion valve and evaporator. The units create noise and start at irregular times, so they should be sited away from bedrooms.
Warranty	Panels 25 yrs, Sol•Flare 5 yrs (expected life 20+ yrs) Solar panels carry a 25-year manufacturer's product warranty and a 30-year performance warranty. SolFlare carry's a 5 year manufacturer's product warranty and is designed to last 20+ years.	Inner tank 7 yrs, compressor and electronics 3 yrs Leading heat pump brands offer a 7-year inner cylinder warranty and a 3-year warranty on the compressor, condenser, expansion valve and electronics. After 3 years, cover is replacement parts only, without labour.
Maintenance	Maintenance-free No scheduled servicing is required. Solar panels may need an occasional hose down.	Regular servicing required Air filters, evaporator coils and condensate drains must be cleaned every 6–12 months. Refrigerant and pressurised lines need annual inspection to protect against micro-leaks and verify compressor performance.
Cold climate performance	Efficiency improves the colder it gets Solar panel light-to-electricity conversion efficiency improves as the cells cool.	Efficiency worsens sharply under 10°C Heat pumps rely on a refrigeration cycle, so their efficiency (COP) drops significantly in winter, often below 2.0 when ambient temperatures fall under 10°C, and frost defrost cycles reduce it further.
Mains power consumption	Occasional Mains top-ups Mains is used only when the sun hasn't brought the cylinder up to temperature.	Consistent Mains draw-down The compressor and fan draw mains power every heating cycle, day or night, all year, and the backup element draws more in cold weather.
Positioning	Indoor or Outdoor	Outdoor only
Cylinder Replacement Cost	Low Cost Electric Cylinder When the electric cylinder fails, it may be replaced with any low cost standard electric cylinder, typically costing $1,500 - $2,000.	High Cost Full Heat Pump When a hot water heat pump fails, it will require a full heat pump hot water replacement, typically costing $7,000 - $12,000.