Whatever Happened to Small Wind?

As of July 2013 there were 16 small wind turbines in the Shoalhaven and surrounding areas. But many of these have been high profile failures and have since been taken down.  So does small wind power have a future? And is your property suited to small wind?  To find out, we asked Katie Ross*, small wind expert at the Institute for Sustainable Futures, who spoke to REPOWER Shoalhaven's Chris Cooper.

The turbine on the hill above Gerringong during it's short existence

Chris: Firstly, what size wind turbines are we talking about here?
Katie: Small wind turbines are defined as those between 1kW and 100kW in size.

We’ve seen some notorious wind turbine failures up near Gerringong and Shoalhaven Heads. What went wrong?

Small wind was over-incentivised early on in NSW and the market wasn't in a position to handle the demand which came. There were no guidelines for systems requirements and installers often did not have sufficient skills, nor were there many opportunities for them to gain the required skills.

There was one Gerringong company, Rewind Energy, who installed over 300 wind systems in NSW. Unfortunately, they were missing some key components such as braking mechanisms (which shuts the system down in high wind events), and slip ring technology (which stops the vertical tracking axis from over-twisting). As such, these turbines failed – which is what you saw on the South Coast. With the supplier having no idea how to respond to the flood of problems, Rewind went bankrupt, leaving the turbine owners in the lurch.

On top of this, most early installations in NSW were on very short towers – you really need tower heights of around 30 metres to get the good wind! 

Despite these well-known failures, are there reliable small wind turbines out there on the market?

Definitely! Small wind is not as simple as small PV, so you need to be careful. There are some brands which have been proven over the years with consistent quality, such as Soma (which are Australian made), Bergey Windpower, Southwest Windpower, Proven Energy and Rutland, which are more for marine installations.

What site attributes would you need to make it worth installing a small wind turbine?

Having the right site is critical for getting a good return on your investment. Here are some rules of thumb:

• ideally have a 300m radius of relatively clear open land around the turbine
• have a tower height at least 10m taller than anything within a 150m radius
• install no more than 300m from the connection point to minimise cabling costs
  
• you need an average annual windspeed of at least 4.4 metres per second  (at the tower height)

How do I know if the installer knows their stuff?
You’ll need to do your own homework on the installer or supplier. Here are the 8 key questions you shouldn’t be scared to ask them before deciding whether to do business with any supplier or installer:

1. How long have you been in the business?
2. How many systems have you installed?
3. How many of your systems are still up and running?
4. Can I speak with any of your customers? (then go and call their customers for feedback)
5. What certifications does your product have?
6. How long is the warranty (aim for 5 plus years) and does it include parts and labour?
7. Is the installer Clean Energy Council certified?
8. How tall are your towers? (if they don’t sell anything over 24 metres high, don’t take them seriously)

How much do they cost?
Small wind systems cost between $6 to $12 per installed watt, depending on brand, turbine size, tower type and other factors. Whilst this upfront cost is more than solar PV, wind systems can generate over 50% more energy per kW than a solar PV system, assuming they are installed in the right spot. 

To make a decent return at the moment (without a high feed-in-tariff) you need to have the ideal site, have the right sized turbine on a tall enough tower, and use the power that is generated to offset your own electricity demand. Then the economics might stack up and it might be a nice complement to a solar PV system, particularly if you're off the grid.

Thanks so much Katie for your time!
Not a problem, my pleasure!

Want to know more?  Click here to access our small wind information toolkit, which is full of resources kindly provided by Katie.

*Katie Ross has 4 years of experience in designing small wind systems in the USA and co-developed and taught the NSW Government Small Wind Site Assessment Training course in 2011.

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