Why Modeling is the First Step
sustainability as the accumulation
of a series of incremental steps
When people hear that Windward has undertaken the task of modeling sustainable systems, most people focus on the "sustainable" part of that mission statement. That's understandable, since sustainability is an important goal, but the purpose of this article is to talk about how to get there -- the modeling part -- and why modeling is a key component of successful research, development and implementation programs.
Nature is a vast web of interactive systems, some profound, some very subtle, but all of which are a part of the dynamic process we have to interact with successfully in order to achieve any meaningful degree of sustainability. We can't say that we only want to deal with the parts we understand -- we have to go beyond that which is where modeling comes in.
Cutting the top off of a 20 gallon propane tank
Note: fuel tanks have to be properly purged before you do this
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It's important to draw the distinction between research and engineering. Engineers work within a well-defined and fully established set of principles, whereas research is what you do when you don't know what you're doing. Research is when you intentionally push back the limitations and barriers that keep you from doing what you want to do.
While it is possible to hire engineers to build some component of a large scale sustainability project, that rarely works out well. It's not just that the engineers don't have a large body of experience to work with, it's also a problem in that the folks who are going to have to operate the unit rarely have a functional understanding of how the system works, and more importantly, what to do when it doesn't.
The building and operating of small systems is important because it allows for the learning curve to work its magic, and it's much easier to modify a small system's design to incorporate what you've learned. This is especially when it's been put together from readily available materials, and dumping the contents and starting fresh is a lot easier with a twenty galllon model system than it is with a thousand gallon production-scale system.
a water pressure tank that will serve as a heat shroud for the gasifier
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For example, we're currently putting together a gasifier to fuel the large, out-door traditional oven that we'll be using to make pizza, bake bread and slow cook beans. The core container that will hold the wood chips was made from a discarded twenty gallon propane tank, and the heat shroud is from a discarded water pressure tank.
If the design doesn't work out, we're only out some shop time since both of these items were on their way to the scrap yard when we intercepted them, and so we can easily afford to take what we learn from this first model and use that knowledge to build an improved version. This way we don't run the risk of being wedded to this implentation of the design because we've tied up a lot of capital in it.
Art Krenzel is an engineer with many years of experience in the field of community-scale composting and the anaerobic digestion of wastes to produce methane gas, and one of the people who's advice I seek out and take to heart.
Recently, Art posted a rant on the gasification list about how many sustainability projects are built too big, too fast, and with a "turn key" mentality that fails to appreciate the need to master the fundamentals. The almost inevitable result is that they seldom perform up to their potential, and even worse, they often wind up shut down only to serve as impediments to the next person who wants to invest serious money in making their operation more sustainable.
Here's what Art had to say.
One of the basic facts of life is that people who do something they love in life consider other related things to be a pain in the butt and just don't do them. Take the dairy industry - the diary farmers LOVE to milk cows. ANYTHING that takes them away from milking cows is a negative experience and not in their scope of work. They sit on a mountain of high energy manure and whine.
In a general way, Americans have the attitude that to make something work, you just jam a key in it and turn it over. If it does not start in 10 seconds, you throw it away and buy a new one. No great thought of why it does not start or what might be wrong because it takes them away from what they love.
They are missing the old guy who used to put his ear to the tank and listen to it gurgle each day and knew when something was different before the whole darn thing went south. We are lean, mean, drive shiny pickups and if we can't do it with a loader, it ain't gonna get done. We have distanced ourselves from understanding nature in the chrome world of 220 volts and diesel fuel.
I can give you the example of perhaps 30 dairy biogas facilities that you can see from the road as you drive south on I-5 through California which have failed. All the metal is there but the units are shut down. Why? Something was probably added to the feedstocks of the biodigester (great ones are , seasonal dietary changes, diesel fuel or hydraulic oil, salt or other concentrates) causing an upset in the digestion and the unit slows way down.
Well, the manure coming in is at a constant rate so it accumulates for 30 days while this finicky biodigester, which they know nothing about, slowly re-establishes itself to production. After several of these upsets and trainwrecks in their manure handling system, they just throw the key away and shut it down. Never to understand that they were probably to blame for the upset and consider it too complicated for them to run.
Vintners are even more extreme. They LOVE wine! Anything which expands their focus from wine making costs too much money and isn't any fun. So, what you and I would consider a challenge to use a process which would return the organic matter back to the soil, is advanced rocket science for them AND IT COSTS MONEY AND IT ISN'T ANY FUN. So they don't do it and whine that they have a pile of crushed grape skins that smell bad and draws flies. The local health department makes them haul the mess off to the landfill because they don't take care of it.
That is why producers of organic wastes whine about having huge piles of organic matter with no where to go. They do not visualize themselves as a partner in a larger life process or a cycle and what they LIKE to do is only a small part of that total cycle.
This is my version of the problem. There are many solutions to these problems but when fuel costs were in the $5 per MM BTU, it was cheaper to buy fuel and whine about the problem than making the investment to become self reliant. Perhaps with $16+ per MM BTU other solutions will surface such as methane production via biodigestion and composting.
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