Monday, 23 July 2012


Response to Jenny's concerns about the wind cluster.

By Scott Willis and Chris Freear.


Jenny's opinion piece last month asked some good questions and thanks to the Blueskin News for the space to respond. Additionally, the BRCT office is contactable by phone and in person (though Friday afternoons, after 3pm is best) for any particular queries about the project. We'll be brief and answer Jenny's points.

  1. Jenny is correct that community wind doesn't protect our substation from any disaster that may befall it. The proposal is for a grid-connected wind cluster, so in the event of a power outage there will be no additional security that comes from
    it to Blueskin. It is possible that over time we'll be able to isolate our section of the local grid but we're nowhere near that point yet.
  2. Wind resource assessment and economic modelling is ongoing, with an independent review underway of the latest technical appraisal after now 14 months of monitoring (the first assessment was done after four months' monitoring). One of the important things in a project of this nature is not to rush appraisals and or make hasty decisions based on incomplete technical data, or single turbine type modelling. But rest assured Jenny, your maths is correct on the early figures – the proposed wind cluster (modelling the windflow 500 turbine) has a capacity factor of 29%. In NZ today our hydro system has a capacity factor of 45% north island, 55% south island. Capacity factor is the ratio of actual productivity against the theoretical maximum and typical capacity factors for wind are in the 20-40% range (the best wind generation in NZ has a capacity factor of 46%). There are sites within Blueskin with a better wind resource than the proposed site – however an economic site is determined by other factors: cost of development, ongoing maintenance, turbine type, etc.  The upshot is that the returns that we expect from this site are in line with other wind developments in other parts of NZ, and further technical appraisal, potentially with an additional hub height mast, are being done and being organised. The purpose of this technical appraisal is to ensure that the risk assessment is as complete as it possibly can be. We're confident at present that the electricity won't be any more expensive than any other electricity, but will in addition provide community value. The project will not fly otherwise.
  3. Control of power supply, unless you're off-grid like Jenny, is not simple (and not necessarily simple when you are on-grid either!). Building energy resilience with whole community benefit will involve compromise, simply because of the range of challenges. If we do nothing, however, then we can be assured of 'business as usual'. With enough community wind clusters and solar installations around the country this will change (how is anyone's guess). At first we'd expect that like with milk - the price will be set by the 'market'. But we will be selling into that 'market' so if prices are high so will the returns to the community owners of the wind cluster and if prices are low the returns will be low but so will our power bills.  Steps in the right direction we'd argue.


On the other issues raised by Jenny:

·                   Group bargaining with the gentailers: theoretically possible. Any such negotiation would be enabled by proving we are a collectivity.

·                   Each household as active energy managers: under the current political/regulatory climate it is simpler for most of us to do things like insulating our homes and adding solar/wetback hot water to reduce our dependence. These actions build our energy literacy up and may help us become future prosumers (producer/consumers).

·                   Back of the envelope solar-smart grid alternative proposal: always good to have ideas, particularly about solar, however at present the average household is not easily able to be cheaply retrofitted and these systems are best done at the household level. When we add in the cost of storage etc., the system will be approximately 5x more costly per watt as the projected cost of generation from the wind cluster.

The wind cluster proposal as it stands does not build physical security of supply but rather builds financial resilience to escalating power costs. By becoming a generator and consumer of approximately the same volume of energy we can effectively remove the corporate profits from the community's net electricity costs, which we believe is a small step in the right direction, but not the last word in terms of resilience.


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