Energy Mix and Renewable Energies – New Zealand
Hydro-‐electric power in NZ: Why and How In 2009 70% of New Zealanders electricity came from renewable sources. In the past New Zealand has garnered up to 91% of its electricity from renewable sources. Water power (also known as hydro-‐electric power) is the main source of renewable energy in New Zealand, generating over 50% of the country’s electricity. New Zealand’s largest rivers, the Waikato in the North Island and the Clutha in the South Island, flow though several large dams and power stations, where the fast moving water can be converted quickly and easily into electricity. However, hydroelectricity is subject to the weather and New Zealand's heavy reliance on hydro has been exposed in past ‘dry winters' when hydro storage (lake levels) has dropped, requiring careful management. Also, while Hydroelectricity produces no air pollution or greenhouse gas emissions it has been identified as generating other adverse environmental effects. The disruption of river and riverbank eco-‐systems by the creation of dams and reservoirs poses a great threat to both native migratory fish species and riverside dwellers such as the highly endangered Black Stilt. New Zealand’s waterways still have the potential to create environmentally friendly renewable energy through hydropower with the establishment of smaller hydro-‐electric stations. Because small hydro energy schemes often do not require dams or significant storage they usually result in significantly less impact on the environment than large hydro schemes. Small hydro schemes are projects below, roughly, 10 MW (megawatts) in capacity. This includes micro-‐hydro, which is usually less than 10kW and is used on domestic applications. There is currently over 160MW collectively of small hydro schemes (of a size less than 20MW) already installed in New Zealand (enough to provide electricity for over 80,000 houses) and the potential for additional small hydro generation capacity is substantial. What are the biggest potentials concerning renewable energy production in your country and what obstacles hinder a higher degree of their use now or in the future? In New Zealand almost one third of our total energy consumption comes from renewable sources. This total includes electricity, heating, and transport fuels. Two of the most promising sources of renewable energy in New Zealand are wind energy, which has already been substantially developed in New Zealand, and ocean energy which is still in the early stages of its development. Wind: As of February 2010, New Zealand had an installed wind generation capacity of 497 MW. Wind power now provides enough electricity to meet the needs of 160,000 New Zealand households, or approximately 3% of the country's electricity demand. Wind farms with a further capacity of 80 MW are under construction, with approval granted or being sought for another 2,875 MW. Although wind will probably never account for a very significant part of New Zealand’s energy usage it is valuable in that it provides greater diversity in the way electricity is generated in New Zealand and thus wind farms make the country less vulnerable to power shortages. A further advantage is that wind farms do not emit greenhouse gases and while wind farms can stretch over substantial areas of land the area around the actual wind turbines can continue to be used effectively for agriculture and farming. Additionally, in future, wind power is expected to become even more cost-‐effective as turbine technology gets cheaper. A current issue concerns residents in affected areas expressing concern about the visual impact of wind turbines on their rural landscape and many instances communities have lobbied against the installation of wind turbines so to protect the natural aesthetics of rural New Zealand. Ocean: New Zealand has large ocean energy resources but has yet to harness their massive potential. TVNZ reported in 2007 that over 20 wave and tidal power projects are currently under development and from 2008 to 2011, the government Energy Efficiency and Conservation Authority has allocated $2 million each year from a Marine Energy Deployment Fund, set up to encourage the utilisation of this resource. The greater Cook Strait and Kaipara Harbour offer the most promising sites for using underwater turbines. Two resource consents have been granted for pilot projects in Cook Strait and in the Tory Channel, and consent is being sought for a project sites at the entrance to the Kaipara. Other potential locations include the Manukau and Hokianga Harbours, and French Pass. The harbours produce currents of up to 6 knots with tidal flows up to 100,000 cubic meters a second. These tidal volumes are 12 times greater than the flows in the largest New Zealand rivers and thus provide an exciting prospect for a country greatly concerned with the furthering of renewable energy production.
RENEWABLE ENERGY = 73% (Graph wasn’t attached) Sam Lusk