Tag: solar power

A sustainable energy future for NZ (without all the hot air)

This is a guest post by Phil Scadden, a regular commenter at Hot Topic (bio at the end of the post). Phil’s interested in energy issues, and has spent a considerable amount of his personal time developing an overview of New Zealand’s energy issues, inspired by the approach used by Cambridge physicist David MacKay in his recent book Sustainable Energy – without all the hot air. I’m very pleased to say that Phil is making his work available via Hot Topic (PDF here), because the perspective he brings provides a starting point for the strategic energy debate we need to be having. Over to Phil:

Sustainable Energy – without all the hot air by Cambridge physicist David MacKay is an excellent and highly readable book of numbers about the questions associated with sustainable energy (available as a free download at www.withouthotair.com). As an advocate of sustainable energy, he describes himself as “pro-arithmetic” rather than a campaigner for one type of energy production over another, which is surely what informed debate needs. Rather than dealing with daunting numbers, he reduces energy calculations to units of kWh/person/day. 1kWh is the unit we pay for in our electricity bills — the energy used by one bar heater switched on for one hour. If you want to prioritise savings then you need to read this book. Turning off a cell phone charger when not in use for a year saves the energy found in one hot bath. “If everyone does a little, then we will achieve only a little”.

The majority of MacKay’s calculations are done for the UK, and I was interested in a New Zealand perspective. To this end, I have used a similar approach to look at two questions.

  • Can New Zealand maintain its current per capita energy consumption without fossil fuels and, in particular, can we live on renewable energy sources alone?
  • How can we achieve a BIG reduction in our personal and national energy consumption, in order to reduce our power requirements?

The detailed document (about 20 pages) can be downloaded here, but this is a quick overview.

Currently 30% of NZ’s energy comes from renewable generation. My calculations (based mainly on 2007 data) show that NZ has the potential to increase this to nearly 100% over the next few decades, thus eliminating fossil fuel use, while still maintaining our current per capita energy consumption (assuming no significant population growth). We could do this initially with new hydro, geothermal and wind generation, while large-scale solar and marine technologies are promising options for the future. Biofuels are feasible but only at the expense of considerable agricultural intensification.

Continue reading “A sustainable energy future for NZ (without all the hot air)”

Obama’s new pathways for power

Barack Obama is matching his words with action. Four days after his MIT speech on renewable energy he has announced, under the Recovery Act,  $3.4 billion in grants to improve the US electricity grid. The grants go to 100 partners with plans to install smart grid technologies in their area. The government money will be matched by industry funding for a total public-private investment worth over $8 billion.

The announcement was made in a speech at Arcadia, Florida, where he was visiting a solar energy centre to open a large-scale solar power plant. In a vigorous statement he explained why the improvement is necessary and what it will accomplish. Continue reading “Obama’s new pathways for power”

Wind, water and sun are all we need

Climatechallenge Wind, solar and water sources are sufficient to provide the world’s energy by 2030. Scientific American has a front cover article coming up in November to demonstrate that. Written by Mark Jacobson (left) and Mark Delucchi, it’s heartening information according to a Stanford University report. Turning away from combustion to electricity from renewable sources results in a striking lowering of global power demand. The reason is that fossil fuel and biomass combustion are inefficient at producing usable energy. For example, when gasoline is used to power a vehicle, at least 80 percent of the energy produced is wasted as heat. With vehicles that run on electricity, it’s the opposite. Roughly 80 percent of the energy supplied to the vehicle is converted into motion, with only 20 percent lost as heat. Other combustion devices can similarly be replaced with electricity or with hydrogen produced by electricity. The authors estimate a consequent 30 percent decrease in global power demand, which is a promising start and helps to make renewables ultimately cheaper than fossil or nuclear generation.

Continue reading “Wind, water and sun are all we need”

US should aim for 80% by 2020

Renowned American environmentalist Lester Brown offers measured optimism in an article published in the Washington Post on Sunday. He claims a surprisingly dramatic 9 percent drop in US carbon emissions over the past two years and the promise of further huge reductions.  Part of this decline, he acknowledges, was caused by the recession and higher petrol prices but part of it came from gains in energy efficiency and shifts to carbon-free sources of energy, including record amounts of new wind-generating capacity. He looks ahead to the prospect of further reductions.  

Continue reading “US should aim for 80% by 2020”

Ten technologies to save the planet

As the news on climate change becomes increasingly serious it is all the more important to affirm that the problem has solutions provided the world applies them soon enough.

Prominent UK environment writer Chris Goodall surveys some of those solutions in a well-researched fashion in his new book, Ten Technologies to Save the Planet.  In combination he shows them adequate to the deep reductions of global greenhouse gas emissions needed over the coming decades.

On the renewable electricity front he explores wind power, solar energy and the tides and waves of the oceans.  Where fossil fuel continues to be used for electricity he considers carbon capture and storage a viable technology and one which carries with it the additional possibility of extracting carbon dioxide directly from the atmosphere for sequestration. Combined heat and power technologies through fuel cells and district heating plants using biomass offer significant emission reductions. House insulation and airtightness, including refurbishment of existing houses, are easy gains.  On transport, he points to the fast advances in technology for battery driven electric cars, and to the large number of companies working on developing biofuels from cellulose. Wood part-combusted to make charcoal and dug into the ground both sequesters carbon and in many soils improves fertility. Finally, he details various better treatments of soil, trees and plants to improve their carbon-sink properties.

All the technologies Goodall canvasses already have solid indications of technical feasibility. Some of them, such as wind power, are in substantial operation. Together they present a credible world in which we could live in reasonable comfort and in a great deal more safety than our current path offers. There are further technologies, such as nuclear energy, which Goodall discounts but for which others make a strong case.

Altogether there is good reason to feel encouraged. We can decarbonise our energy and our industry.  We are not doomed to destruction for lack of alternatives.

Why then, in view of the utter urgency of the need, isn’t the world in general and New Zealand in particular getting on with it?  Goodall feels obliged to evaluate the technologies in terms of their cost relative to fossil fuel. But why should competitiveness with fossil fuel matter as much as it still seems to? We now understand that the continued burning of fossil fuel is dangerous for the human future. The fact that it may be cheaper in economic terms doesn’t lessen that danger.

Within a market economy, Goodall urges measures to put a price on carbon either through direct tax or through capped emissions trading schemes.  He points out that a high carbon price (he suggests US$50 per tonne) would make almost all the technologies in his book competitive very soon.  Against those who say the economy would be crippled he argues that in fact the impact on GDP will not be large.

But even if it were large, governments cannot allow the burning of fossil fuels to continue unhindered.  The new technologies have to be adopted as rapidly as possible – by regulation and subsidy if market signals are not sufficient.

Unfortunately, many politicians remain scientifically ignorant and vulnerable to vested interests. Our own new government is still dithering, possibly even back-pedalling, on the modest measures adopted in the emissions trading scheme.

The recent calm and impressive statement of President-elect Obama may herald a new urgency. Announcing that he planned to reduce US 1990 emissions by 80% by 2050 through a cap and trade system and direct government investment in clean energy, he concluded: “Delay is no longer an option. Denial is no longer an acceptable response. The stakes are too high. The consequences, too serious.”

This column first appeared in the Waikato Times on 9 December 2008