Wind energy FAQs

There are laws in place to ensure wind farms are only developed where they are appropriate.
Anyone wishing to develop a wind farm must seek resource consents from the relevant authorities (the regional, district and/or city council), under the Resource Management Act (RMA).
Wind farm developers must also prepare and submit an Assessment of Environmental Effect (AEE) reports with their resource consent applications.
AEE reports help ensure local authorities are aware of the full details of what is proposed and the potential effects including visual, noise, communications interference, ecological, archaeological impact and effects on culturally significant sites.

Most of the sound produced by a wind turbine is a broadband noise, a swishing sound created by the rotating blades. Design improvements have greatly reduced sound levels, and if you stand directly beneath a modern turbine, you can easily have a conversation without raising your voice.

Like other forms of environmental sound, such as airports, ports or construction, wind farms must adhere to an appropriate or relevant noise standard. The standard ensures that while wind farms will be audible at times, the level of sound heard at a location will be at a similar level to the natural sound in the background – such as wind in the trees.

The limits of the wind farm noise standard are also intended to provide protection against sleep disturbance and maintain a reasonable amenity at locations surrounding a wind farm.

In 2010, Standards New Zealand updated the wind farm noise standard (NZ6808:2010). The standard was originally developed as an aid to planning consent procedures and to provide guidance on the limits of acceptability for sound received at locations near with wind farms.

Changes to the standard are intended to provide greater protection for communities by addressing and clarifying issues such as cumulative effects, special audible characteristics and noise predictions.

With the increasing use of wind energy world-wide to generate electricity, concerns have been raised regarding possible health effects. The main concerns relate to low frequency sound and infrasound, shadow flicker, blade glint and electromagnetic interference.

Some of the reported effects include anxiety, sleep disturbance and hearing loss. Over recent years, a number of international studies have been conducted, all of which have found no evidence to support any adverse health effects.

In 2009, an international panel of experts was established to review the literature available on the perceived health effects of wind turbines, with a specific focus on sound produced by the turbines¹.

Following extensive review, analysis and discussion, the panel concluded:

The panel also gave consideration to ‘wind turbine syndrome’ and vibroacoustic disease (tissue inflammation and fibrosis associated with sound exposure), both of which have been claimed as causes of adverse health effects. ‘The evidence indicates that ‘wind turbine syndrome’ is based on misinterpretation of physiologic data and that the features of the so-called syndrome are merely a subset of annoyance reactions. The evidence for vibroacoustic disease is extremely dubious at levels of sound associated with wind turbines’.

A similar review was undertaken in July 2010 by the National Health and Medical Research Council for the Australia Government. It too concluded that ‘There is currently no published scientific evidence to positively link wind turbines with adverse health effects².

¹ Wind Turbine Sound and Health Effects: An Expert Panel Review. http://www.canwea.ca/pdf/talkwind/Wind_Turbine_Sound_and_Health_Effects.pdf

² Wind Turbines and Health. A Rapid Review of the Evidence, July 2010, http://www.nhmrc.gov.au/publications /synopses/new0048.htm

Internationally, poorly sited wind farms constructed many years ago have been associated with bird mortality, but these wind farms are now becoming an exception.

While any tall structure poses some risk to birds, the impact of wind turbines on bird mortality rates is low if careful consideration is given to how the wind farm location fits into the natural ecology of the area.

In the past Meridian has used human spotters to identify and count bird species. This has proven time consuming, expensive and challenging due to difficulty in accurately tracking the altitude and paths of flocks of birds. In 2008, Meridian purchased the most advanced and tested Avian Radar System on the market called Merlin XS2530e. The Merlin environmental surveyor is one of the most powerful tools available for the assessment of proposed wind farm sites. When used in conjunction with human spotters, Merlin generates a detailed data set which can be used to accurately track migratory birds and ensure the wind farm is designed to to cause minimal impact.

Merlin will further inform the already detailed ecology studies which identify what types of birds are in the area, and enable proper siting of turbines to avoid flight paths and significant habitats. Overseas studies show that, in general, birds will become accustomed to wind turbines and learn to avoid them.

In the case of the Brooklyn wind turbine in Wellington, which is located on the boundary of Zealandia (formerly Karori Wildlife Sanctuary) there have been no recorded incidents of bird mortality in its 15 years of operation.

Wind farms need to be built in locations where they can make best use of strong, unimpeded wind flows, such as hilltops and ridgelines. This can make wind farms a striking and impressive feature on the landscape, a visual effect that many people like but some do not.

The visual effect for local residents is a significant consideration when potential sites for wind farms are investigated.

Meridian applies a clean site philosophy to its wind projects that minimises the visual impact of the project, in particular the roading and substation placement.

The internal electricity networks are kept underground wherever possible, the turbines have no branding and Meridian undertakes a comprehensive vegetation reinstatement programme after construction.

Small increases in blade length can significantly increase the energy output of a turbine. This means fewer turbines, fewer roads, smaller project footprint, and lower maintenance cost. As turbines have got larger, the rotor speeds have decreased. This has dual benefits, from both a visual and ecological perspective.

From an environmental perspective, wind energy is one of the best new generation options immediately available in New Zealand, because wind can’t be used up.

Fossil fuel alternatives emit greenhouse gases on an ongoing basis, and most other renewable options have smaller capacities, longer lead times, or are more expensive.

Wind farms reduce greenhouse gases when they displace generation from thermal sources, such as coal, which emit greenhouse gases. Building wind farms means less thermal generation is needed from thermal power stations and that ultimately fewer thermal power stations will be built.

Public opinion indicates that wind energy is the preferred option for generating electricity in New Zealand. Research conducted in 2008 by the Energy Efficiency and Conservation Authority (EECA), a government agency established to encourage, promote and support the uptake of energy efficient initiatives and new renewable energy, showed that 91 percent of people nationwide see wind energy as having a positive impact as an energy source for New Zealand in the future.

Wind power is unlikely to ever replace other forms of generation such as fossil fuel or hydro power stations.This is because the wind does not always blow consistently enough, though New Zealand has strong winds when compared with most other countries. This makes wind power generation much more reliable here.

On average, New Zealand wind farms generate twice as much electricity when compared with international wind farms. Generally speaking in New Zealand, you can expect a wind turbine to be generating for over 85 percent of the time, at a reasonable site with a good wind resource.

Wind farm opponents often suggest that due to the variability of wind, every wind farm should have an equivalent amount of back-up generation from another generation source. However, New Zealand’s electricity system already provides additional capacity (some 3,000 MW) should there be a failure at a generation plant or the temporary loss of the Cook Strait cable.

New Zealand is fortunate to have excellent resources for producing hydro electricity.

Meridian Energy meets approximately one third of New Zealand's electricity needs from its hydro power stations in the South Island.

Hydro power is a key part of the New Zealand electricity generation mix, but it is vulnerable to low rainfall and limited future development options.

Meridian can now complement its hydro stations with wind power. When it rains, the lakes fill and we can generate from hydro power. When the wind blows, we can generate electricity and the water in the lakes can be conserved for times of peak demand.

Currently in New Zealand, only hydro power stations, geothermal power stations and wind farms are economically viable means of generating renewable energy on a sufficient scale.

Gas is another generation option, but there is no certainty as to whether gas can be supplied to power generation plants in the future. Oil, gas and coal generation emits greenhouse gases.

Other renewable energies such as solar electricity or wave/tidal power are currently very expensive or in the early stages of commercial development.

Community and stakeholder consultation is an important part of Meridian’s development process and the resource consent process because it is crucial that people have an opportunity to have their points of view considered on energy development projects.

People are welcome to attend open days, request meetings with the consent applicant, or make submissions as part of the consent process for proposed wind farms.