Posts by Andrew Stevenson
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The Genesis willow operation raised some issues besides the production of ethanol from woody biomass.
In the UK, where they do coppice willow for biofuel (direct combustion, not ethanol), they mix species in order to reduce potential damage from bugs/fungus and other biological nasties as chemical control is too expensive - the Genesis approach is to pick one variety and monocrop, which leaves them open to this risk.
The byproducts they will extract, like wood sugar, are also produced by China - any guesses who will control the price?On the corn/food production point, I think a lot of the production in the Waikato is for stockfood (could be wrong) and so you could say that human food production will not be affected...
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Another bus story:
On Penang Island in Malaysia when one of the people I was travelling with started to come down with a kidney infection. A plan was concocted to head towards Bangkok in case advanced medical treatment was required, the problem was that the trains had stopped running. So we hired a old merc taxi to get us over the border into Hat Yai in southern Thailand and from there an overnight bus to Bangkok.
We were seated up the front of the bus; which is aggressively airconditioned to about 10 degrees and we have no warm clothing, a Thai horror video is played at full volume and the seats are suited for Thais - who are on average a foot shorter then me. So we're cold, bewildered and uncomfortable, but worst of all we can see the road ahead. Roads are rudimentary and traffic is comprised of either motocycles loaded to gunnels with people and produce or trucks loaded much the same. The bus driver considers all traffic infront of us a personal insult that must be overtaken. If in the middle of an overtake, oncoming traffic appears, the driver decides on the basis of how many headlights he can see whether to drop back or keep going and force the assumed motorcycle to the side of the road. "Please god, don't be a truck with a headlight out" was the constant refrain through my chattering lips.
Cap this off at the end of the trip with a taxi ride across Bangkok in rush hour, which is NOT stop/start but more like some cross between a giant pin ball machine, kinetic sculpture and adventure park ride... -
From the Diversa Press release
Statements in this press release that are not strictly historical are "forward-looking" and involve a high degree of risk and uncertainty. These include statements related to...Diversa's ability to discover and develop enzymes designed for cost-effective wood biomass conversion. Such statements are only predictions, and the actual events or results may differ materially from those projected in such forward-looking statements.
In other words 'We have an idea, we don't know if it will work'. It seems a bit early to be saying we can use wood based ethanol to replace tranport hydrocarbons when they have not got wood based ethanol working yet...
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The point is plant biology will be the answer
I've found the next logical step for Michael's problem, we all become trees!
Back in the real world, I think Stephen has it with the balancing of supplies and needs. Biomass, efficiency, hydro, etc will all need to be integrated in order to solve the problem. The demand side is a bit more tricky; fuel poverty, local impacts, global variations in energy use, needs vs wants etc
Maybe the pellets are not perfect, but using them is better then waiting for utopia or a silver bullet.
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Michael, from your arguments it sounds like we should ban free firewood - its obviously a huge source of particulates, after that we can work on the vehicles.
As for switching to electrity, please tell me where it is going to come from and how you are going to get it into Christchurch?
PV for the houses? Be cheaper to burn money in the fireplaces...
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All pollution is compliant until ruled otherwise.
Cute soundbite, but there are urban emission standards for domestic wood burners now.
Why can't compliance and best practice be the same thing? And veering back on topic, what part of the pellets will lead to disaster? -
All the pellet fires are emissions compliant, if you can control the fuel supply and fire design you've pretty much got the air quality problem solved. There was some problems with wood (log) burners operating on low output and people 'de-tuning' their fires, resulting in more particulates produced; but I think the pellet fires had solved this one.
Stephen Crawford raised a good point about the when waste products (like fish and chip oil) become commodities in their own right - your 'free' fuel becomes subject to supply and demand. Might not be an issue with the amount of waste wood we produce here not. But when we start to see wood fired central heating, process heat and co-gen then supply might start to get squeezed.
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Please excuse my spelling, I'm an engineer.
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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 independant consumer advocate has another view then I start to get sceptical.
The cost comparison of panel heater and heat pumps is from this BRANZ report from the DBH review of energy efficiency in buildings. See section 9 page 23 which details the cheapest option for a given heating energy use. It looks like you use about 4,000 kWh in winter, so say 5,000 per year and this is below the change over point even at 5% discount rate. Average heating energy in NZ homes is about 3,900 kWh pa (fromm HEEEP year section 3.3).
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I can't see the methodology for the Consumer results, but it is fuel and not total cost based. Adding in the other factors for a total cost of ownership would give a significantly different result - on this basis heat pumps are more expensive then plain electric panel heaters. Average figures from Consumer (reading of a graph with ranges so a bit rough) was;
pellet burners 11c/kWh
wood burner 8c/kWh
Heat pump 8c/kWh
Panel heater 20c/kWhI couldn't see the BRANZ HEEP study, your link was to an MfE report based on a phone survey. The HEEP studies have found significant issues with self reported energy usage, which is why you need to measure everything.
I did see the data for Christchurch - $15/month is very good given one 20kg bag of pellets will heat a home for 28 hours on low and costs around $8.50. That's less then 2 hours heating per day in winter...Kyle: I think those were firelogs, a different thing (and more expensive then pellets)