NZ CLIMATE TRUTH 52
JULY 3RD 2004
The latest statistical Review of World Energy (2004) is now available, and can be
downloaded, ordered, from
It provides Tables of
Oil; production, consumption, proved reserves, price, refinery capacity and trade
Natural Gas production, consumption, proved reserves and trade
Coal production, consumption, proved reserves
Nuclear Energy consumption
Primary Energy, consumption by fuel
plus numerous graphs and pie charts.
It firmly denies that there is a world shortage of oil. There are proved reserves
for 40 years.and natural gas for 60 years. They should, perhaps, also explain that
"proved reserves" would hardly ever exceed these figures, since it is not worth
prospecting for any more. There are "resources" or as-yet unproved reserves which
well exceed these years. Price fluctuations are mainly caused by political events.
Current oil prices are similar to those of the 1980s.
Proven coal reserves are good for 200 years. After a decline in world consumption
from 1996 to 2001 there was an increase since 2001 of 17%, almost exclusively in
the Asia/Pacific Region (which increased 33%), mainly in.
China (at 54%) , This means that the Kyoto Protocol. which is supposed to reduce
emissions of carbon dioxide from fossil fuels in developed countries, is aimed at
the wrong target.
I am copying here a portion of the Global Warming and Cooling News No 7 which was
distributed by my fried Dr Gerrit Van den Lingen of Canterbury University on June
Last month, after overcoming many hurdles, including environmental objections, the
Christchurch company Windflow Technology ltd, built its first wind turbine at
Gebbies Pass. I went to have a look and took some photographs, one of which is
herewith attached. This wind turbine, named Windflow 500, is developed by Windflow
Technology ltd. It is planning to build up to ten turbines at a cost of around $2
Information on the turbine can be found on its website (www.windflow.co.nz). One
interesting piece of information is their “Windflow 500 Power Curve” (attached
herewith). This graph shows that the turbine needs at least 24 km/hr winds to start
generating. It reaches its maximum generating capacity of 500 KW at wind speeds of
about 51 km/hr.
This has interesting consequences. For instance, Christchurch has lately
had unusually warm and sunny autumn weather. Large anticyclones were
centred over New Zealand, and there was hardly any wind. Under these
circumstances the turbine would not have been able to generate
electricity. This highlights one of the drawbacks of wind power: NO WIND,
NO POWER. This means, as many people have pointed out, that wind power
always requires a back-up generating facility, most likely thermal power
Furthermore, as maximum generation of 500 KW is only reached at wind speeds of about
51 km/hr, for much of the time it will generate less.
For our energy calculation below we have therefore used the figure of 250 KW
uninterrupted generation from the Windflow 500 turbine.
Superficially, wind power sounds very attractive. It is renewable and (apparently)
environmentally friendly. As Windflow Technology ltd writes on their website:
“Sites for further hydro dams are limited by technological and ecological
restraints, but the supply of fossil fuel is also limited and may become
increasingly unpredictable. Perhaps even more important is the threat of climate
change associated with fossil fuel emissions. Thus we need to move towards
renewable, non-polluting sources of energy.
Wind energy meets those demands. It produces zero emission, it is
renewable and abundant, it can meet New Zealand’s growing demand of energy
without compromising sustainability and it provides a more cost-effective
solution than new hydro generation.”
These statements require some careful analysis. I would like to address two points:
1. that wind power can meet New Zealand’s growing demand for energy.
2. that wind power has zero emission and can generate electricity without pollution
and is renewable,
1. Future electricity requirements are driven by two major factors, one – the
depletion of the Maui gas field (see above), and second – the increase in
demand due to an increasing population and growing economy. It is not always
easy to obtain all the right statistical energy figures, but as far as can be
ascertained, to replace gas-based electricity generation with wind power would
require about 8000 Windflow 500 wind turbines.
In recent years, electricity consumption in New Zealand has increased by about 3 %
per year. It is expected that by 2015 extra generation is required equal to 5 Clyde
dams or three Huntly power stations. That is about 2200 MW, or 8800 Windflow 500
Therefore, if wind power were to meet growing electricity demand and replace natural
gas, we would require 16,800 wind turbines by the year 2015. To put this into a
geographical-physical New Zealand context – it would mean one wind turbine per 16
square kilometres, or one on every 4x4 km block of land. This certainly would turn
New Zealand into a quaint tourist attraction.
2. As far as I am aware, New Zealand has at present two wind farms, both in the
North Island. One is the Tararua Wind Farm in the Tararua Ranges. At present it has
48 Vesta V47 (Danish) 660 KW turbines, and a further 55 are planned. The second is
the Hau Nui Wind Farm (Hau Nui is Maori for “Strong Wind”), situated about 20 km
from Martinborough. It has 7 turbines.
In the Autumn 2003 issue of the glossy architecture/style/design magazine URBIS is
an advertisement from Milburn Cement company, drawing attention to the fact that
their “Holcim Ultracem” cement has been used for the foundation of the wind turbines
at the Hau Nui wind farm (pages 28-29). This advertisement provides the following
Each wind turbine tower weighs 67 tonnes and has to face wind gusts of up
to 120 knots (about 200 km/hr). To give such a structure a secure footing
requires 270 tonnes of concrete and 10 tonnes of reinforcing steel. Of
interest for this discussion is the fact that cement fabrication by its
very nature produces a lot of carbon dioxide. Therefore, wind power has
only zero emission after it has been fabricated and installed.
Furthermore, the fabrication of the reinforcing steel as well as the
materials for the wind turbine (steel, copper wiring, plastic, etc)
requires a lot of non-renewable energy input. Therefore, it will take a
lot of time before a wind turbine starts to produce a positive energy and
environmental balance return.
If we take the above calculated number of 16,800 wind turbines required to meet
growing demand and to replace the Maui gas, and take the concrete/steel foundation
figures for the Hau Nui wind turbines, this would mean 4.5 million tonnes of
concrete and 168,000 tonnes of reinforcing steel. Add to this the materials for the
wind turbines themselves – 1.1 million tonnes of steel, copper and plastic, and we
get a picture of the consequential scale of the assertions that wind power can meet
future energy demands without environmental costs.
NOTE. The above calculations are based on the best information available to me.
Other people have come to different conclusions. For instance, in the 2002 Annual
Report of the coal-mining company Solid Energy, they state that the increase in
electricity demand by 2015 is the equivalent of 5 Clyde dams “or 20,000 wind