This is a guest post by Phil Scadden and Oliver Bruce (bios at the end of the post), who have updated to Phil’s 2009 paper Sustainable Energy Without the Hot Air – A New Zealand Perspective, which was published at Hot Topic. Inspired by the approach used by Cambridge physicist (and now chief climate change advisor to the UK government) David MacKay in his book of the same name, they bring a common sense perspective to the strategic energy debate we need to be having. Over to them:
Sustainable Energy – Without 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/day/person. 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 understand the which actions actually save energy (and which are just hype) 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. Phil was interested in a New Zealand perspective and so published the original paper at Hot Topic in 2009 (found here). Oliver read McKay’s book earlier this year, came across Phil’s work (thanks to John Peet at Phase2 for the referral) and with his help updated the figures for 2012.
To this end, we 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?
After completing the updated paper, we had a discussion with Gareth about the best way to publish the work and decided to run the report as a series of posts at Hot Topic. There are two reasons for this:
- Easier to get feedback issue-by-issue from the Hot Topic (and wider) community.
- It makes for a more palatable read than simply giving you folks a 22 page document.
This post today is a quick overview of the changes since the 2009 report, and serves as an introduction to the series which will appear at Hot Topic over the next couple of weeks.
For those that can’t wait, the full updated (2012) document can be downloaded here. Note it may end up being revised as your community finds errors in our work, so it might be better to wait till we’ve completed our series!
THINGS THAT HAVEN’T CHANGED SINCE 2009
To begin, it might help to outline the things that haven’t changed since the 2009 report that Phil wrote. Based on our calculations NZ still has the potential to increase our energy generation to nearly 100% renewable 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 phasing in large-scale solar and marine technologies as they become more economically feasible in the future. Biofuels are feasible but only at the expense of considerable agricultural intensification, or on marginal agricultural land if the price of oil ranged around $200.
In short, New Zealand transitioning to 100% renewable energy in the next 20-30 years is very doable, but it will require some difficult decisions.
NZ is energy-rich, but every option using renewable sources has its own problems. If we don’t like the environmental and other consequences of the available generation options, the only alternative is to reduce our power requirements. Vehicle fuel is NZ’s largest energy use (about a third of our total) so savings in this area have the potential for greatest significance. Optimistically, we might be able to reduce our energy needs by up to 25% by 2030, by savings and improved technology (especially electrification of transport). We’ve gone into a bit more depth on the electrification of electricity in this report given that a few factors have combined since the last report that indicate this is the most probable future. More on that in a later post.
CHANGES IN OUR ENERGY USE SINCE 2009
The things that have changed since the last report is that our both our per capita energy consumption and costs of transitioning to a 100% renewable future have declined, while our renewable energy generation has increased.
We’ve been through a prolonged recession since 2007 (the year of figures available when Phil was writing the last report), and this has impacted on energy use like elsewhere in the developed world. According to the Energy Data Files from the Ministry of Economic Development, we’re using the equivalent of around 5 kWh/d/p less than we were in 2007. This reduction comes from a few different areas. The Tiwai aluminium smelter is using about 1kWh/d/p less energy now than it was in 2007, which is a pretty big chunk of energy. There is also a noticeable decline in transport fuels, which correlates with the news about Kiwi’s driving less on the back of the doubling of petrol prices. Finally, our population has increased by 6% in the five years since 2007, meaning there are more people to divide the energy consumption (kWh/d) across.
We’ve also seen an increase in the amount of energy coming from renewable energy sources. All the wind power that has come online since 2007 has added the equivalent of 1.6kWh/d/p to our energy generation total, while the new geothermal capacity has added around 1.4 kWh/d/p. While this is great, it should be noted that we use around 88 kWh/d/p, so these numbers don’t do anything substantial to change our energy mix. We’ll explore this when we get into our posts on geothermal and wind.
Finally, the costs of increasing our renewable energy capacity over the next 20-25 years to 100% using the same ‘energy plan’ model adopted by McKay has come down. In 2009, Phil calculated that these changes would cost anywhere from $81-163 billion dollars and involve new renewable energy capacity, the electrification of transport and some energy efficiency measures. Our revised calculations have this figure at around $70-75 billion by 2025, with lower costs for insulation and the electrification of transport than previously outlined.
This is a large figure, and it goes to show that this isn’t something that we can do for free. It will cost money, and it would require commitment from across the political spectrum to make it work. We’ll be cover the costs in one of our last posts after exploring all the options.
So, from here on out, we’ll be posting regularly on our various options starting tomorrow when we get into Post 1: The Renewable Energy Challenge. We hope you follow along and provide your thoughts and questions.
Oliver and Phil
Phil Scadden is a Dunedin-based geoscientist/number-cruncher working from GNS Science Ltd. While professionally involved in the thermal modelling and hydrocarbon geochemistry of sedimentary basins, he is also keenly interested in energy and leads a GNS project investigating thermal power efficiency from the perspective of fundamental thermodynamics. The investigation here is a private work.
Oliver Bruce is a young Kiwi based in Doha, Qatar where he works in industrial business development. He graduated from College of the Atlantic in the USA, where he studied politics, ecology and business. He has long had an interest in renewable energy and climate change, and was part of the youth delegation to the Copenhagen Climate Summit. He credits Phil with doing the intellectual heavy lifting in this work– he just did some number crunching.