Category: Climate science

Sustainable Energy NZ #11: How can we make road transport more efficient?

Welcome to the eleventh post in the Sustainable Energy without the Hot Air – A New Zealand Perspective series. After our previous posts on hydro power, geothermal and wind (and a summary on the big three), solar, biofuels, marine and waste energy, we’re now looking at answering the question:

How can we achieve a BIG reduction in our personal and national energy consumption?

We covered the breakdown of where we use this energy in the last post. Today we’re dealing with our biggest chunk of energy use: road transport.

A few notes before we begin: as before, 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’ve been looking to replace around 55 kWh/d/p of energy currently generated by fossil fuels.

Cars

About a third (31kWh/d/p) of our total energy use is spent on vehicle travel, which is high by international standards. (This figure also includes some diesel purchases by small farmers and transport operators that are not adequately captured by other statistics.) Incidentally, one litre of petrol contains ~10kWh of energy, so at a national scale, we’re all using around 3 litres of petrol/person/day. By comparison, the average UK citizen spends 14 – 16kWh/d/p on personal vehicle travel.  Consider that the average NZ car drives 18,000km in a year. If all were medium SUVs (0.9kWh/km) with 2 people in them, then this would translate into only 22kWh/d/p. It is clear then that we must make a lot of single-passenger trips in inefficient vehicles. Worse, this works out at a staggering 46kWh/d per vehicle (excluding mopeds, but including trucks)!

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It’s Global Warming, Stupid: telling it like it is in post-Sandy USA

GlobalWarmingStupid

Sandy was an astonishing storm ((See Jeff Masters for some of the reasons why.)). Bloomberg Businessweek has taken the opportunity to state the obvious and create one of the great magazine covers to sell the story ((The ageing magazine editor in me doffs his hat.)). It’s worth reading the magazine’s coverage ((Or the parsing of it at Climate Progress.)) because the usual suspects are out there trying to deny the undeniable. Sandy was a storm made worse by the fact of climate change. We all have to live with that.

While the US mops up, and reinsurers check their cash reserves, we can be sure of one thing. The worst is yet to come — and that’s not being alarmist, just pointing out the consequences of unavoidable future warming. That’s truly alarming.

Sustainable Energy NZ #10 – How can we achieve a big reduction in our personal and national energy consumption?

Welcome to the tenth post in the Sustainable Energy without the Hot Air – A New Zealand Perspective series. We’ll be changing gears here from our previous posts on hydro power, geothermal and wind (and a summary on the big three), solar, biofuels, marine and waste energy. From here on out we’ll be attempting to answer the question:

How can we achieve a BIG reduction in our personal and national energy consumption?

It’s a very important topic – and one prone to greenwashing and hype. Like McKay, we want to have informed discussion about the options available to us here in NZ, so we’ll be going through topic by topic and looking at energy use in each sector of our lives: transport, residential energy, the things we buy, and so on. We hope that you find it interesting and informative.

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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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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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