Has anyone got solar panels on their roof?

[sootie]

Don't expect to break even in your lifetime. If you average a power consumption of 25 units a day, the best you can hope for from your system will be 3 kwhrs (3 units) for each of the 2.5 hr average sun hrs/day. there is not much power in the sun before 10 am and after 3 pm.

On a good day you may get 10 Kwhrs or 10 units which will offset your 25 units, so you only pay the utility for 15 units.

You will still be paying a daily supply charge and about 25 cents a unit, the utility will usually want to pay you wholesale rates of 5 cents a unit if you actually have any power to sell to them. some Power companies will pay more, up to retail price.

We don't have the govt incentives to help pay for these installs like Germany, Spain and USA because our energy is already mostly generated by renewables anyway.

Rick.

A good cost/benefit analysis please, or do we agree the return in NZ is very poor?.
I really am quite a society conscious guy, but if my third great grandson breaks even, because he happens to be still living in my house in 50 years, assuming all the solar panels are still working - that is getting pretty esotreric!
I am easily convinced that reducing power consumption reduces the bills, but this is a separate issue.
As you observe, it still does not get around connection charges either - you have to disconnect to get that bonus.
I agree about the renewables. Actually, I would like to see NZ make use of the natural dam effect our land mass has on the ocean & generate more tidal power in Cook Strait. If we put the engineering effort in, this one is a runner, but Kiwis are not too good at being first in these areas.

[paturoa]

Oh, and grid tied systems don't use any batteries

There are actually two types, first is the no battery version that you refer to and the other will feed back to the grid when the batts are fullly charged.

[paturoa]

I was reading a web site several months ago about a home built solution in Canada. They installed a new (2nd hand) hot water cylinder before the main cylinder. The solar panels ran through to a 24v direct imersion element in the cylinder that was always on.

Start up costs were the panels and mounts, cables, switch, imersion heater, 2nd cylinder (which I think was purchased 2nd hand for bugger all) and some extra plumbing including linking the header pipe from both cylinders as they said that the solar cylinder would eventually boil (was a low pressure system).

The idea being to maximise the electrical efficiency and miminise the cost outlay. So basically the grid supply was only requried to boost the main cylinder. The efficiency, cost benefit, break even was extremly good from what I read (can recall).

And no I couldn't find the site again.

[caseye]

Blardy useless ewe r, pity you couldn't. I'd like to have read that article. no Matter, suffice to say if we can generate our own power and are allowed to feed it back into the grid and get paid for it, why the hell ain't we being given every incentive and subsidy under the sun to get it done. Same with water catching and treatment. No underground pipes to break when we get a bit of a shake, no lines to come down on us either.

[paturoa]

Blardy useless ewe r, pity you couldn't.

Been trawling my history and googling, suspect the site has gone.

Anyway was just a couple of panels direct to one of these (or similar).

http://www.orionairsales.co.uk/wind-...24v-1473-p.asp

And while I was googling there were quite a number of hits where a wind genny was used instead of panels into immersion heaters, so looks like a resonably common solution.

[spanner spinner]

Looking at getting a grid connected solar system on the roof. Just thought I'd see if anyone has one and if there are any 'good to know' things. Probably getting 3kw

My father has a 3kw system on his garage roof, it is well worth doing. Grid connected is the best system for most people who are currently connected to the grid as it cuts out the battery cost which can be over half of the cost in a properley set up solar system. I use to work for telecom building remote phone distrbution sites and microwave radio sites a lot of which where solar powered, so I have just a bit of experence with solar setups.

Couple of bits of advice learnt the hard way with my fathers set up. If you are looking at a 3kw system get a 5-6kw inverter as it is easyier to just add more panels later if you want more power rather than have to upgrade most of your setup. It is also cheeper than having to replace the smaller inverter with a larger one if you want to upgrade later as the cost diffrence between 3KW and a 6KW is not that much compaired to the cost of the rest of the components in the system. The larger inverter will also run cooler at the lower power and when these units are cool they run more efficiently. Wire in a cooling fan to blow throught the inverter to keep it cool, once again it increases the efficiently.

Have you got your hot water on solar? If you don't have your hot water on solar allready spend the cost of solar hot water on a bigger solar power set up as this is the more cost effective way. Feeding your hot water your own solar power can work out cheeper than the cost of hot water solar panels and plumbing costs.

Do a bit of reading before you go any further, I would recomend getting the book titled "Solar that realy works" & "Solar Success" both will answer most of the questions you have, they are available from Jaycar electronics part numbers are BE-1535 & BE-1537.

Get a inverter that has a inbuilt MPPT solar charge controller (Maximum Power Point Tracking solar charge controller) as this allows you to wire the panels in series to supply up to 120 volts. This means the solar charge will start earier in the morning and to run later in the day, and it allows a smaller cable size to be used which can be important cost wise if there are long cable runs involved in you install. BUT!!!! don't skimp on the size of the cable you run as it dosen't make sense to have to add extra panels because you are losing the power you have generated in you cable runs because the cable is a little on the small size.

If you have a lot of roof area availabe have a look at using amorphous panels rather than the more common monocrystalline. Amorphous panels work better in low light (ie a overcast day) and supply power for more hours each day, but are larger in area in relation to output compaired to monocrystalline. To give you some idea to get the same power as monocrystalline out of Amorphous panels you need 2-3 times the surface area. A perfect set up would use a set of amorphous panels and a matching set of monocrystalline panels, the only drawback is the area of roof that this set up would take.

Hope this answers some questions, message me if you have any questions that I haven't answered.

[jellywrestler]

Looking at getting a grid connected solar system on the roof. Just thought I'd see if anyone has one and if there are any 'good to know' things. Probably getting 3kw

for fuck sake why would anyone admit to having them here? in 5 minutes the mud people will claim the sun then charge us all for the use of it...

[fuknK1W1]

Looking at getting a grid connected solar system on the roof. Just thought I'd see if anyone has one and if there are any 'good to know' things. Probably getting 3kw

Can you get low light intensity panels?
Do you get enough sunshine hours?
Is your roof big enough?

[Winston001]

I have been interested in solar energy and design for 15 years. I did what I could with our house - orientation to the sun allowing 30 minutes for longitude, deep eaves, and double glazing.

I have not yet moved to solar energy because I'm not convinced of its efficiency. But - the right time is approaching.

The most simple step is solar hot water panels. They work. Nevertheless you need a plumber who knows what he is doing and I don't think they work with high pressure water systems - you need a heat exchanger.

Solar electric panels are very low efficiency - about 5%. However the technology is improving and I think Sanyo have new panels in the 15-17% range. Just be aware that solar panels are vastly below water/oil/gas/coal generated electricity. As indeed are bio-fuels but that's another topic.

If you are keen then go for it. I plan to in about 7 years time.

[sootie]

I have been interested in solar energy and design for 15 years. I did what I could with our house - orientation to the sun allowing 30 minutes for longitude, deep eaves, and double glazing.

I have not yet moved to solar energy because I'm not convinced of its efficiency. But - the right time is approaching.

The most simple step is solar hot water panels. They work. Nevertheless you need a plumber who knows what he is doing and I don't think they work with high pressure water systems - you need a heat exchanger.

Solar electric panels are very low efficiency - about 5%. However the technology is improving and I think Sanyo have new panels in the 15-17% range. Just be aware that solar panels are vastly below water/oil/gas/coal generated electricity. As indeed are bio-fuels but that's another topic.

If you are keen then go for it. I plan to in about 7 years time.

Absolutely spot on common sense mate! I agree with every word!

[Edbear]

For everything you need to know about solar, get in touch with Europlumbing, www.europlumbing.co.nz they will not only advise the efficiency of all the systems and the latest technology but specialise in designing bespoke systems tailored to the individual requirements of the home.

And for the record, I was advised that our house didn't warrant solar as we are on mains gas for water, cooking and warmth. The cost-benefit didn't add up enough to make the investment worth it. So they won't just try to sell you a system.

Quality and experience? They do large commercial sites including schools and have a ready to go kit for hot water systems that is effective and economical and a lot cheaper than others on the market.

[sootie]

For everything you need to know about solar, get in touch with Europlumbing, www.europlumbing.co.nz they will not only advise the efficiency of all the systems and the latest technology but specialise in designing bespoke systems tailored to the individual requirements of the home.

And for the record, I was advised that our house didn't warrant solar as we are on mains gas for water, cooking and warmth. The cost-benefit didn't add up enough to make the investment worth it. So they won't just try to sell you a system.

Quality and experience? They do large commercial sites including schools and have a ready to go kit for hot water systems that is effective and economical and a lot cheaper than others on the market.

I do agree that going solar can be worthwhile.
The most obvious example I know of was on a station far out in the Aussie outback. Endless sun, electricity and other energy sources at a big premium. Virtually no corosion maintenance issues either.

They got it right too - huge solar panels for direct heating of a vast amount of hot water. They employed 30 stockmen who came home most nights, and immediately wanted a hot shower late afternoon. Very hard to argue with the economics of this one!

These days they probably generate most of their electricity from the sun too. Real estate is not much of a problem on an outback station in Aus either!

[Swoop]

The most simple step is solar hot water panels. They work.

A work colleague researched solar panels a year ago and determined that the government should assist people getting into solar hot water heating with a scheme like the "warm up" campaign. A loan that gets mainly paid back over a few years would make a significant dent in power bills.

His other finding was that NZ does not maintain the panels. European systems have ongoing maintenance to keep their systems in good order, where we fail to do that and just make a repair when eventually needed...

[steve_t]

A work colleague researched solar panels a year ago and determined that the government should assist people getting into solar hot water heating with a scheme like the "warm up" campaign. A loan that gets mainly paid back over a few years would make a significant dent in power bills.

His other finding was that NZ does not maintain the panels. European systems have ongoing maintenance to keep their systems in good order, where we fail to do that and just make a repair when eventually needed...

Solar water heating is subsidised in NZ. Solar generation isn't

Maintenance is a must!

[SPman]

I'd suggest that you look at the cost and life span of the solar panels. These haven't been too flash in the past.

http://www.energymatters.com.au/inde...aign=EM120918L