Energy self sufficientcy

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Joined: 9 Dec 2009
Energy self sufficientcy

As part of some development id like to do I plan to setup a likely combo of wind and solar to aim for a max of 10 Kw hour and power essentially 2 properties. have people done anything like this and or recomend Wellington contractors, or know of pitfalls or recomendations? I'm afraid Im not one of those handy build anything with #8 wire kinda bloke  so its all double dutch to me at present and so Ill need rely on some honest professionals!


Do any power companies support the buyback? so you can sell excess power produced to the main grid?

Kindest regards


Daryl's picture
Joined: 7 Jul 2008
Electricity is a bonus.

10kw is a big system. $50k - 80k?
We are moving in Jan, then I will set up our system, but I will tell you my thoughts.
First, when building energy resilience, think of electricity as a bonus. Try to design your homes to not need it. Then work up from there. Eg, Lights, laptops, fridge. The goal is to avoid using your renewable electricity to produce heat. Hotwater, cooking, heating. Use Solarwater obviously, but back that up with a woodburner you can cook on. If you have this then you may only need a 1kw system per house.

Buy a centermeter of Trademe and install it in your current house to get an idea of your energy behavior.

Remember you can always add.

Still if you want to go large...
There seem to be a few 6kw wind turbines around for $30k installed,(proven Lower hutt) (to be a good site for wind the trees on the property should show some deformation from the wind)

You might like to check out

As for grid tie, most power companies will give you unit credits, but not cash. (meridian might pay??)Right House are supposed to help you on that (but I have rung them twice and then never call me back)
SO the best you can do is only have to pay the line charge unless you can sell your surplus to your neighbor. The benefit of going grid tie is you dont need to invest in batteries, how ever, if there is a power cut then you only have what is being generated at that moment. So no cooking or heating.

If you go off grid, then you really look after yourself, how ever the upfront cost is large, and you limit what you can do to the size of your system, eg cooking with an oven or using a welder might be out of the question. Also if you have an overcast week with no wind, you might find your selves hanging out at you mums place.

I would like to hear if anyone is getting paid $$ for the electricity they are producing.

Joined: 4 Jul 2008

Hi All,

We had a 2kw system, 1kw in solar and 1kw in wind, when we were off the grid in the far north. This was plenty to keep our house of 2 adults and 2 children ticking over. It gaves us lights, fridge ( never liked gas fridges as when they go wrong your house burns down as has happened to 2 different friends of ours!), televison, stereo, laptop etc.

Grid interactive is the way to go as battery management sucks big time. My understanding with grid systems in NZ is you get paid the base wholesale rate, which doesn't really make it that viable from a $$ perspective.

In my opinion larger community owned infrastructure is really the way to go with grid interactive systems as you get a bigger bang for your bucks.


Joined: 5 Jun 2009
Renewable energy


Im a renewable energy consultant. I am originally from the UK originally from Totnes home of the beginings of the transition town!! It was great to be involved. I can give you a bit of advice on the subject. I am pretty much up to date with all this stuff here in NZ after working for a company here. Ill give you all the advice for free My goal is just to get as much renewables in as possible. I can also give you a list of installers and rough price estimates. It gives me a chance to help Aotearoa's transition.

e mail

Joined: 25 Sep 2011
Unless you are living in an

Unless you are living in an area with a constant supply of wind I would be inclined to stick with solar and use a generator as a backup. The reason for this is that wind is considerably more expensive per Watt then solar. It is also a lot higher maintenance.

If you are undertaking this project with the intention of making a profit through FIT's (Feed in tariffs) I would not bother. Yes, the grid is expensive, but compared to alternative energy it is still cheap. Furthermore I am not aware that any company will pay you for net electricity. (ie: You won't get paid for returning any more then you use).

Even if you could get paid - in my opinion (and this is an ideological perspective) why would you want to sell them your clean electricity? (note: clean in this case means high quality electricity free from spikes, surges and other crap).

If you are going to embark on this project I strongly suggest you keep it for yourself. You may want to try living on 10 units (10kWh) per day for awhile and you will most likely conclude you have no surplus.

Other advice includes:
1. Do not, whatever you do, buy on price. Spend the extra and stick with well known brands. While there are some areas in life we can economise, alternative energy is not one of them. If you need 1st hand experience of how low cost systems can be real crap spend some time in an area where there is a lot - from really good to really bad - like Great Barrier Island.

2. Do not ever consider a 12V system as the cabling is too awkward and the upgrade path too restrictive. Go with 24V or 48V.

3. Use all 230V appliances until you really know what you are doing. A so-called "12V system" is not in reality 12V, but is 10V to 16V (aproximately) and there is very few items that can handle this sort of voltage swing. (note: multiply my numbers by 2x and 4x give or take for 24V and 48V systems).

4. While they are a lot more common these days, make sure that any inverter you buy is pure sine wave. "Modified sine wave" inverters are nothing but trouble and false economy. For the sake of saving a few bucks you will be buying something that will cause you agony and even premature failure with a lot of equipment. But this kind of relates back to point 1 - only buy quality.

Scott Willis
Scott Willis's picture
Joined: 2 Jul 2008
Grid tied electricity for householders

Hi All,
From our Blueskin experience:
1. Off grid households (generally) work well with householders who are practical DIYers, and there are a number of businesses in most regions who can set up good systems or assist individuals do that.
2. It makes good sense, whether grid tied or off grid, to first work hard to reduce electricity consumption, as Darryl stated above.
3. Current regulations do not facilitate grid-tied households and in fact this National led government seems antagonistic to any system that might aid that (Gerry Brownlee essentially said "No feed-in tariff under my watch" in Feb 2011).
4. ReFIT NZ is a national lobby group with a great deal of knowledge about FITs. Their website is here (but may not be working at present...). In addition, we (Blueskin Resilient Communities Trust [see:]), 350Aotearoa (Ashlee) and Nelson Environment Centre (Carolyn) have a project with Stephan of REFIT to work on some proposals for rules to allow distributed generation - something that is essentially legislated against under the current market rules. This is very low key at present, but please get in touch with one of us to register an interest if you're keen to be active on this front.
5. At a political level, the Green Party favours legislating for distributed generation.

In the practical here and now, I know of one household in our community that is grid tied with solar and wind generation and has a 1:1 arrangement with MERIDIAN (i.e. Meridian will pay for electricity generated at the house the same sum it charges for it when it is consumed at the house). Line charges come on top of that. This arrangement was negotiated directly between the householder and Meridian and currently Meridian seems to offer the best deals of all Gentailers to householders for grid tied generation. You need to be aware that there is no legal requirement for gentailers to purchase your electricity under currently regulations, and so you will not receive any long term contract, making bank loans, etc, difficult.
In addition:
-- Meridian, currently a S.O.E may well be partially privatised depending on the next government, and may well change its 'green community good' offer.

In addition to our community wind cluster project we are building on the existing energy initiatives in the Blueskin zone, and are aiming to develop a public trial zone for integrated household energy systems and expect to have many more practical examples to share in time.

While I think it is very important to work at the level of our individual households, I think we can achieve more if we work as a community as well - sharing resources, costs and increasing effectiveness. That's not to say you should not build as much generation into your house as you can if you have the resources! Just that such action will allow even greater resilience if it is accompanied by some larger group action and political action, as without a change in our national network grid connection is only as good as the national grid.

Scott Willis
Scott Willis's picture
Joined: 2 Jul 2008
Regulation for Distributed Generation

Refit NZ - the charitable trust working to deliver information on the advantages of rules for DG - is offline at present due to an unfortunate death.

In any political forums people may attend between now and the election you may like to ask whether politicians would like to create a 'level playing field' to allow the growth of distributed generation in NZ - a country blessed with renewable generation opportunities yet with remarkably little at a household and community scale. With the intended privatisation of our electricity SOEs there will likely be a halt on investment in new generation by those SOEs. This will have two immediate consequences:
1. They don't spend money therefore there will be higher returns for investors in those ex-SOEs.
2. The actual cost per kW hour will go up.

Side issues are that any move towards security of supply (a government goal) and affordable electricity will go on the back-burner.

With gas running out and no replacement generation we are looking at price hikes.

So where do our politicians stand on regulating to allow DG fill the gap?

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