Q. Why put the cylinder on the roof.
A. It is the most efficient place and it creates space inside your home. The less parts, pumps and circulating water the less wear and tear.
Q. What heats it when the sun doesn't?
A. Electric element same as conventional system.
Q. How hard is the SunTrap to install?
A. If you are handy with home DIY it wont be too much trouble to fit the frame. Then you need a plumber to complete the plumbing.
Q. How does the SunTrap solar hot water compare to a PV solar grid tie system.
A. A 3kw grid tie system will cost $9000 installed and would save you $360-$405 per year. A SunTrap solar hot water system will cost less than $5000 installed and save you $800-$1100 per year.
Q. Does solar hot water need consent from the council
A. The SunTrap system is a 'controlled' solar hot water system. If the home owner installs the unit themselves and the plumbing/electrical component of the installation is completed by suitably qualified tradespeople, consent is not required.
Hot water systems that are not 'controlled' systems i.e. when you have a cylinder inside your house and and circulate the water through a heat ex-changer on the roof will always require consent.
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Q. How long does it take to heat one of these if it gets emptied? Say, for example, if I used it to fill my hot tub.
A. Approximately; If you filled up the hot tub at 9am you would have 60 degree water in the tank by 5pm (20°&sunny) consider that you would only want the temp of the tub to be 39-40° this is easily achieved on an overcast day. Factor in not having a hot tub every day say every second you will always have hot water at the ready as the tank is well insulated and will "build" on the previous days heating.
Q. What if one of the tubes break, will I still have hot water?
A. Water does not circulates in the tubes. You will still have hot water. The glass of the tubes is very strong and not likely to break even in a hail storm, however they are easily replaced if required.
Q. Is solar hot water worth while?
A. Short answer: YES. Long answer: If you borrowed 100% of the cost and put it on your mortgage you would pay it off and have extra money in your pocket. E.g. $4500 on your mortgage at 4.5% paid off over 10 years would cost you $47 per month. If the SunTrap hot water system saves you $100 per month in electricity you have an extra $53 per month to go towards what ever you like. Doesn’t sound like much you say? On a $300k mortgage an extra $53 per month would reduce it from 30 years to 28 years and save you over $20k in interest.
Other important factors to consider here;
(i) When the hot water system is paid off in 10 years you will have the full $100 in your pocket.
(ii) Electricity prices will increase so your potential saving will increase with this.