Posts by David Haywood
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The second of a two-part series on biofuels. This episode looks at a potential New Zealand biofuel that could provide a large proportion of our transport energy -- and which is also derived from forestry...
NOTE: A complete transcript of this episode is available here.
Further information:
-- Read or listen to Biofuels, Part 1.
-- Read more about bioenergy at Scion.
-- Visit the Diversa website.
This episode of Public Address Science was originally broadcast on Radio Live, 2nd June 2007, 2 pm - 3 pm.
Public Address Science dedicated RSS feed
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Jolisa,
It's great to see you emerging from your winter hibernation. Encore!
RE: latest P & P film
I completely agree that McFayden did a much better job than silly old Colin Firth -- although I admit to confusion in terms of Donald Sutherland's concept of playing Mr Bennet with a Canadian accent: "I'm just going ooot to visit Mr Bingley". Quite mysterious.
I also thought the film did a nice job of highlighting the wealth gap between the Bennets and Darcy/Bingley/etc., but I can't help feeling that there's yet to be a successful realization of P & P on the screen. Each version seems to have its own (major) flaws.
I've never been to Iceland, but a friend once called from Reykjavík to say that she'd spent €90 on a pizza. The trauma was such that she needed to phone someone in New Zealand for counselling.
This rather gave me the impression that food can be a bit pricey in Iceland -- so it may be wise to give the kids a good feed beforehand.
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a short, snappy and easily agreed upon gender-neutral title that will piss off neither males nor females
I can answer this one: Citizen (Cz for short).
As in Cz. Anjum Rahman
RE:
Brick Haywood
I'll add it to our list...
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Bart Janssen wrote:
Can we run a competition to name your child?
By awkward co-incidence, Jennifer's surname is 'Hay'. So we've already had the suggestions of:
-- Hayden Hamish Hay Haywood
And the inspired combination of Maori and Heywood R. Floyd tribute:
-- Heywood Heihei Haywood-Hay
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Stephen, Rob, Hadyn, Deborah, and Ian,
Thanks for the kind words! All joking aside, we are incredibly pleased and happy. Although, admittedly, there is also a very large dollop of panic.
Hadyn:
'Moro Barsley' is superb (my mum will be delighted).
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Andrew:
This is drifting away from the topic of this discussion, but BRANZ seems to pull through some quite strange assumptions from their thermal modelling results.
For example, BRANZ seems to assume that you need two heat-pumps worth $5000 (in total) for a house like mine. In reality, I have a single $2000 heat-pump.
Unless I'm reading this table wrong, then it certainly doesn't apply to my heating situation, and (I doubt) that of many people in this country. Maybe they're using old pricing figures?
But using their energy pricing and discount assumptions for my $2000 heat-pump: I get a total present value of $8218 for capital + energy costs, compared to $11,584 for a resistance heater over 25 years. I make $3366 (yay for me!) -- but, more importantly, I help stop the country from building another Huntly power station or two...
RE:
The devil is in the details when it comes to methodology used in studies. But when the proponent of a technology has glowing (pardon the pun) findings and an independent consumer advocate has another view then I start to get sceptical.
I know what you're saying here, Andrew. But I don't think there's a conspiracy between a "glowing finding" from Scion and "another view" from 'Consumer Magazine'. In my opinion, "among the cheapest heating options" is still a fair description of the situation -- particularly when you consider the range of possible operating conditions (e.g. heat-pump in Invercargill vs. wood pellet burner running under an optimum control regime). However, I would certainly agree that from the studies I've seen you couldn't describe the wood pellet burner as the cheapest heating option (although it's still a hell of a lot cheaper than some other options, e.g. an open fire).
But thanks for the debate -- it reminds me of being back at engineering school! Perhaps what this highlights is the lack of a comprehensive and rigorous study of this issue. It would also be interesting to see some numbers on public good vs. private good in terms of heating systems.
P.S. Spelling excused!
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Andrew:
Sorry, I was writing at top speed and somehow pulled the wrong title through from my spreadsheet -- that'll teach me to double-check my links before I post (I've corrected the report name in my original reply).
Yes, as you point out, this does give rather a dramatic illustration of my point about methodology.
I could (and probably should) also have pointed to this report from the University of Otago Wellington School of Medicine and Health Sciences (which compares heat-pumps, gas, and pellet burners).
Lifetime costs (capital plus operating costs) over a 20 year life: pellet burners’ and heat pumps’ overall lifetime costs are almost identical. Gas heaters are the most expensive. A sensitivity analysis shows that if electricity prices were to rise significantly (e.g. by 10%) heat pumps would become more costly than pellet fires. This appears more likely than a rise in pellet prices (or gas prices).
I'm not advocating for wood pellets vs. heat-pumps (or anything else), but I'm just trying to point out that the methodology dramatically affects the results of exact comparisons. Given that some of these studies are more than a bit vague on describing their methodology then this is why I chose to go with Scion's rather more general "among the cheapest heating options" line.
P.S. By the way, are you sure that the lifetime costs of a resistance heater would be less than a heat-pump? We use about 32 kWh per day of heat over the four winter months in our house in CHCH. In round numbers (at an electricity price of, say, $0.15/kWh) that would cost about $6000 over, say, a ten-year lifetime. Given our mean temperatures and the quoted COP of our heat-pump, then it should be able to provide the same amount of heat for around $2500. Since the capital cost of the heat-pump is only about $2000 then it seems to me like I should be well ahead on lifetime costs (just doing the numbers in my head -- it's not an inflation-adjusted calculation, or anything).
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Andrew:
George is still getting back to me on a number for the energy yield ratio (obviously he didn't make it in time for the programme). I'll post an update as soon as I hear back.
In terms of the relative cost of wood pellets, I was going by the published figures I had seen from various studies (although I have not seen the latest 'Consumer Magazine' information) -- as well as information supplied by Scion, as follows:
Several studies have shown that wood pellets are among the cheapest heating options on the New Zealand market
See also this document.
As you'll appreciate, the costs arrived at are partly dependent on the type (and complexity) of the analysis used. For example, do they consider the capital cost of the burner/heater, the cost of compliance with emissions restrictions, maintenance costs (chimney sweeps?), the cost of time spent by the end-user maintaining/fuelling the system; what assumptions do they make about length of operational life, what assumptions do they make about operational climate (obviously the lower mean winter temperatures make a heat-pump much less efficient in Invercargill than in Kaitaia)?
To illustrate: the 'Warm Homes Technical Report' suggests that wood pellet systems are the least expensive household heating method in Christchurch (see this link, Section 19.2, Figure 19.2).
For this reason, I preferred to go with Scion's general statement about wood pellets being "among the cheapest heating options". But I'm certainly happy to be corrected if more up-to-date scientific data has shown Scion's claim to be incorrect.
Are you able to post a brief summary of the 'Consumer Magazine' data and methodology? What do they give as the cost differences between wood pellets and other low(er)-cost forms of heating?
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Michael:
If you're pointing out that biofuels currently use fossil fuels in the planting, tending, and harvesting processes then I agree.
What I said was:
... from this perspective, biofuels can be said to be carbon neutral, because it's theoretically possible to manufacture and use them without adding to the overall amount of carbon dioxide in the atmosphere.
The key word here is "theoretically". The point I was trying to make is that it's possible to grow biofuels without adding to atmospheric carbon dioxide levels (i.e. without use of fossil fuels), so long as the crops are continually replanted. In fact, it's even theoretically possible to use the crop biofuels themselves for all the processing energy inputs. This is not done at the moment, but there is no scientific obstacle to it (in theory).
In contrast, of course, fossil fuels burnt in the ordinary way will always add carbon dioxide to the atmosphere, i.e. they will always be carbon positive (unless, of course, you remove the carbon dioxide post-combustion, and sequester it forever somewhere).
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It's wonderful (and awe-inspiring) to see Merkproduktionz take a genre as tired and clichéd as the musical, and transform it into something so utterly sublime. Who among us would have suspected that the hackneyed cinematic and musicological conventions of such films as 'My Fair Lady', 'Guys and Dolls', and 'Apocalypse Now!' could be so completely turned on their heads, and that it would give birth to such a radical and challenging new art form!
It is a privilege to witness Merkproduktionz growing as an artist, and coming to the realization that we -- the audience -- are growing along with them.
Bravo!