Signing Off

I am regretfully giving up writing regular posts for Hot Topic. Age-related macular degeneration, an eye disease affecting central vision, has been advancing for some years and has come to the point where reading of the kind on which I have depended for my posts has become difficult and laborious. It’s four years since Gareth invited me to contribute to Hot Topic and I have been grateful for the opportunity. The full seriousness of climate change dawned on me about seven years ago and though for a time I had some opportunity to voice my concern through the pages of the Waikato Times, that terminated when the paper started talking about the need to ‘balance’ what I regarded as a straightforward communication of mainstream science.

Happily Hot Topic suffers from no inclination to balance science with denial. It has given me the chance to use the time available to a retired person to read and then review many books and reports by climate scientists and science writers and experts in associated fields. It has also allowed me to express the hopes and fears that mingle in the mind of anyone who understands the urgency of the climate crisis, and to chastise leaders who think we can somehow both mitigate climate change and burn all the fossil fuels.

I turned 80 this year, and my concern over climate change only grows with advancing years. I’m more pessimistic than I was four years ago about the possibility of significant action being taken soon to rein in emissions. But the urging must continue and the science be respected. Gareth stands out in the New Zealand setting for his commitment on both these counts and I have felt fortunate to be associated with his efforts and the support of the intelligent and knowledgeable commenters and contributors which Hot Topic enjoys.

Gareth adds:

It’s been my great privilege to provide a platform for Bryan’s writing over the last four years. In that time he has reviewed dozens of books (click the book reviews tab to get an idea of just how prolific he has been), held the government to account for its wrong-headed policy making and failures of vision, and provided a carefully considered and highly valuable moral perspective on the problem we all confront. If Hot Topic has achieved anything in recent years, it is in no small part due to his efforts — not least in keeping the blog running when I disappeared overseas or on holiday.

Thanks for all your words, Bryan, and the very best of wishes for this latest phase of your retirement.

Sustainable Energy NZ #9 – Here Comes the Sum – what are renewables worth?

Welcome to the ninth post in the Sustainable Energy without the Hot Air – A New Zealand Perspective series. Today we’re summarising the numbers on the various renewable energy options in New Zealand (and finding they’re more than sufficient!). For the background to the work please our introductory post here. Also check out our earlier posts on the potential of hydro power,  geothermal and wind, and the summary on the big three. More recently we’ve dealt with solar, biofuels, marine and waste energy. Note: the units are in kWh/day/person – ie. if you ran a 40W lightbulb for 24 hours, it’d take ~1 kWh over the space of a day. We then divide it by person to give you a sense of the scale of the resource proportionate to the size of the population. Be sure to check out the methodology. For reference – we’re looking to replace around 55 kWh/d/p of energy currently generated by fossil fuels. 

So we’ve gone through the various renewable energy options over the last week or so. So where does this leave us for increased generation potential among renewable options? The affordable, mature technologies are hydro, geothermal, wind, waste gas, solar heating and biofuel. Large-scale solar and marine technologies are really promising options for the future but cannot be realistically considered now.

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Eyes on the prize

A few weeks ago I burned a little midnight oil and, hunched over this very keyboard, wrote a little story about The Last Climate Denier in New Zealand. If you were to think that it was a tad satirical, you would not be wrong. It’s a sad story, set in a parallel universe that bears a striking resemblance to The Burning World, and was my entry in this year’s Royal Society of NZ Manhire Prize (fiction section). Now I learn that by some strange misjudgement my short story finds itself in the shortlist for the prize. I can’t publish the story here until after it loses (which will be late November), but in the meantime you can download it here. It’s a two hankie story, so be prepared…

[The superb Mavis Staples.]

Rising Sea Levels

Of all the consequences of human-caused global warming, sea level rise has always held special alarm for me in its inexorability, its extension into the future, and the enormous disruption it threatens to centres of high population and essential infrastructure. Scientist Scott Mandia (blog) and writer Hunt Janin have teamed to produce for the general reader an explanation of what it will mean for the world in coming decades and beyond. Their book Rising Sea Levels: An Introduction to Cause and Impact is patient and restrained in its survey, but no less sobering for that. Their coverage leaves no doubt as to the magnitude and extent of the measures that will have to be taken to try to cope with the effects of sea level rise as it gathers momentum and extent.

The authors don’t expect much in the way of mitigation of climate change by international agreement to limit emissions. Indeed, they take it for granted that emissions  are going  to continue to rise and that international agreement will continue to founder on obdurate differences between political blocks which negotiators appear unable to resolve even in the face of such a threat as global warming. Presumably one day the common danger will become so overwhelming as to force international agreement, but the authors see no such early likelihood and certainly not in time to forestall metres of sea level rise. The book is not about preventing sea level rise but about preparing for it and adjusting to it.

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Sustainable Energy NZ #8 – The Tides They Are A-Changin’ – the marine and waste energy resource

Welcome to the eighth post in the Sustainable Energy without the Hot Air – A New Zealand Perspective series. Today we’re crunching the numbers on marine and waste incineration potential in New Zealand. For the background to the work please our introductory post here. Also check out our earlier posts on the potential of hydro power,  geothermal and wind, and the summary on the big three. More recently we’ve dealt with solar and biofuels. Note: the units are in kWh/day/person – ie. if you ran a 40W lightbulb for 24 hours, it’d take ~1 kWh over the space of a day. We then divide it by person to give you a sense of the scale of the resource proportionate to the size of the population. Be sure to check out the methodology. For reference – we’re looking to replace around 55 kWh/d/p of energy currently generated by fossil fuels. 

The marine environment offers several possible renewable energy sources, notably wave and tidal energy. Wave energy systems have been studied by the Electricity Authority, and data here comes from their report [yeqtogu]. Feasible wave energy plants need wave energy greater than 20kW/m “close” (say 6km) to coast. New Zealand has 2000+ km of coast-line fulfilling these parameters, mostly on the west coast. Wave derived energies in the far south can be 60 to 80kW/m, which is impressive. That is approximately 86kWh/d/p for a 50% efficient wave generator covering half our available coastline. However, a reality check indicates that no such mechanism exists (so far wave generators have been built for survivability rather than efficiency) and many factors would constrain where wave generators could be built.

A fairly detailed analysis based on currently available technology has identified sites offering perhaps 2kWh/d/p and a maximum potential for perhaps 27kWh/d/p. While a number of prototype and early commercial plants have been deployed worldwide since 2009, this realistically still is best be described as an emerging technology with very substantial environmental and economic barriers to deployment.

Continue reading “Sustainable Energy NZ #8 – The Tides They Are A-Changin’ – the marine and waste energy resource”