That's a lot of questions for a new guy..    The difference between a pumped system and a Thermo system is that with a thermosyphon system your cylinder would be on the roof (over the panels) and no pump is required (gravity fed), no Cylinder in the house, no moving parts and most easy to install very often sold as a complete affordable package. with the pumped system obviously you have a pump that is installed near by the Cylinder which is not on the roof. This system allows for better control of the solar energy intake and has a smart controller option. There are many specialists in this field, I recommend you get as much information as possible before making a decision. If you require a contact in this area, Plumbers.co.nz have installers they recommend. Please email me your details at plumber(at)plumbers.co.nz and ill send you some info.

Solar is worth it , if you've got the dollars go solar with heat pump back up, at worst case scenario heat pump would be still way cheaper than running an electric back up.

The Government offers a $1,000 grant towards the cost and there's now a website you can go to to get EECA approved systems and EECA registered installers. I recommend having a look and getting qualified advice on the approved systems available. They are also offering finance options, may be worth considering?

Solar hot water systems do not use grid electric power yet the system makes hot water. I know you will be happy when you see the first 3 months electric bill reduction. Electric hot water heaters use a lot of electric power. The one in my home has two 1,500 watt heating coils and a 60 gallon tank. A solar hot water heat uses no electric power and can make hot water for free. You decide. Free verses your electric bill.

I think it all depends on how much mullah you want to spend on the system
im just an apprentice but i am getting heaps of exp with solahart systems and what i have seen with them they are well worth the money, but how the boss explains it is 'it is only going to make the savings if you use the water solar has heated' so i guess these systems would only be useful in situations where a decent sized family is usuing the high volumes in the tanks
Ive been to houses to service the units and they have had the power off since late october and still have the power off til around now and are getting decent heatage out of their tank untill this late into the year.

questions like this always make me laugh...


each and every household is different...

the hot water system should be designed around the clients hot water NEEDS

in most cases solar will trump others, generally the only thing that beats solar is geo

most others are about on par with one another - I believe lpg has now been priced out of the market in terms of heating hot water unless low occupancy building use (ie 1-2 ppl)

i believe direct evac tube pumped systems with a GOOD controller to be best in terms of efficiency and performance

much of this is based on locale within the country also

it is foolish and naive to discount ANY particular heating medium without doing some basic calc's - in some cases the good old 100% efficient submerged element can come out on top in life-cycle costing...

food for thought...