对于这个绿色建筑师的休息室情节的第二部分，我们的好朋友帕特·库恩（Pat Coon）再次加入了我们的行列修订热, to discuss the topic of biomass boilers. In the second installment of this epic trilogy, Phil, Pat, and I wrap up our discussion of log gasification boilers and introduce our listeners to the concept of wood pellet boilers. If you missed Part One, you might want to give that a listen first, especially since it gives you the recipe for the perfect red Manhattan (which goes very well with this smoky topic).

In Part Two of the podcast, we discuss:

• Thermal storage for log boilers.
• Distribution. It’s a boiler and can do anything a normal boiler can.
• 维护。维护涉及什么？
• Pellet boilers.为什么考虑弹丸锅炉？不再拖木了。
• Pellets as fuel.
• 维护。
• 它们如何自动化？
• Fuel delivery, by the bag or by the truckload.
• Dust control and your pellet hopper.
• The quality of fuel and its output.

请继续关注第三部分，我们在这里谈论成本和储蓄，菲尔的六位数想法，以及这一集的歌曲选择“ Daydreamer”，作者：Pete Miller.

OFFICIAL TRANSCRIPT

Phil Kaplan: So, let’s talk about crunchy green versus sexy green.

Chris Briley: Well, I’ve said this before. The threshold test is, if you ask, “Well, how do you feel about composting toilets?” And if they actually are interested in hearing what you have to say about it, then you’ve got yourself a crunchy green right there. That’s a crunchy green person. But if they’re like, “Uh, well, hey, I was, uh…” then you know what they are.

Pat Coon: Here’s what we do in our showroom. We have two doors side by side. We’ll both go into the bathroom. We’ll say, “On the left is a composting toilet, and on the right is a flush toilet.” And we’ll see where they go. Then we know what we’re going to sell them. Whip out the solar hot water literature!

Chris: So, what do we talk about cost?

Pat: Let me back up just a minute. Not all wood boilers need thermal storage tanks. If you don’t have a thermal storage tank, you’re really running your wood boiler between November and March. You’re not running it in the shoulder seasons; you’re not running it in summer.

克里斯：我在跑其他东西吗？

Pat: Well, your backup system. Some clients have a woodstove that runs in the shoulder seasons.

菲尔：那么，您是说您可能不需要备份系统吗？

帕特:你知道,你总是需要一个备份系统tem. It’s prudent, and the insurance companies and the banks will want it—because you’re going to want to go away for a week and not worry about the house freezing.

克里斯：这不一定是极端或强大的，只是可以拯救您的东西……

Pat: Yeah, the one we just finished for the mechanical room had an electric boiler. Why spend all that money—just a cheap electric boiler that’s there for that one week when they go away. So, if you don’t have a thermal storage tank, it costs a whole lot less.

Chris: Because it’s cycling on and off more?

Pat: Well, there’s less equipment. But it’s a little less efficient. You’re also tending it every three hours irregardless; you’re not going down once a day and filling it. You’re playing with it more; it’s a more active experience.

菲尔：我的问题是：分发。告诉我们一点。

PAT：任何类型的分销都很好。

克里斯：真的吗？但是它像水一样脱落，对吗？因此，您正在以某种方式在空中进行水或水的水为水。

Pat: Yeah. There has never been a distribution system that we couldn’t attach to, so if you’ve got forced air, we can put a coil in a forced air system. If you’ve got baseboard, we can do that. Radiant floors actually work really well, because they let you pull the tank down further and empty the tank. Distribution is not an issue. The only time it can be a problem is if the house is really under-distributed. You really want to be able to run 150-degree water.

克里斯：关于下部的坦克，这会带来维护。什么样的维护是人们期望的，因为这些东西很重。他们走进地下室；他们不会进入三楼的阁楼或类似的东西。

Phil: They’re really robust. On the tank, with a thermal storage tank, once a year you check the pH and the water level—you have to add 20 to 30 gallons of water. So, once a year you do that. Of course, you have to clean them, and different boilers can be cleaned in different ways. They’re easy or hard to clean. Once a cord of wood, you have to open it up and scrub it out. The new, fancy ones you clean by shaking a lever. The older ones, you have to open some wing nuts; it takes about 10 minutes. Feeding them and cleaning them are small tasks.

Chris: So, now let’s shift the conversation. We’ve talked about logs as a fuel source. Pat, what if I don’t want to schlep the logs? I love everything you just said. I love the renewability of wood, but I don’t want to schlep the logs. Isn’t there a way, Pat…?

Pat: Well, it’s funny you should mention it. Have you ever considered a wood pellet boiler?

Chris: You mean the little thing that’s like a woodstove?

PAT：是的，它们有颗粒锅炉 - 地下室，中央，水力，自动化系统。

Chris: But then I have to schlep all the pellets, don’t I?

Pat: Not anymore. Wood pellets are nothing more than sawdust, which is passed through an extruder—a big drum with holes on the outside that crushes the sawdust and pushes it through the holes. And the lignan in the wood gets squirted out of the cells; that’s what gives it a sheen and holds it together.

克里斯：那么，你能用叶子做到这一点吗？只是在开玩笑。

菲尔：那就是光泽的来源吗？我想知道他们是否正在抛光这些东西。

Pat: Everyone thinks they put a little petroleum on them to hold them together, but no, that’s just the lignan from the wood. So, the whole idea of pellets—why would you do this? One is, when you make the wood into sawdust, you can dry it really easily. For cordwood, nice, dry firewood has 20% moisture content. For pellets, it’s down to around 7%. So you can get a lot of the moisture out, and that makes it burn more efficiently on site and makes it easier to transport. When you “densify” it—when you squish it back together again—you can ship it more easily because now it’s much smaller: about half the volume of cordwood.

Chris: It’s also a gasification process, is it not? For firing the pellets?

Pat: What gasification did was have multiple zones. For most pellet boilers, they don’t have separate combustion chambers; usually there’s one chamber with a combustion zone and a secondary combustion zone, and a heat extraction chamber. So, usually they’re two-chamber boilers as opposed to three, but they still do the same thing. They get up to really high temperatures, they get all the energy out of the wood and suck it all out.

Chris: So, will it yield the same kind of exhaust as a gasification boiler, or will it be slightly more…

Pat: A little cleaner, fewer particulates, higher—a really good wood boiler has about the same thermal efficiency as a really good pellet boiler. But it’s easier to get good efficiencies out of a pellet boiler than a wood boiler. The other thing about the fuel is that it’s uniform, so it’s easy to design an augur system to transport it because it’s only going to be so fat, or so long; it’s going to have certain properties that are knowable.

Phil: Speak a little bit about the augur system. You don’t open this up and dump shovelfuls of this in and light it in the same way.

Pat: Well, you can. This is an important thing to know about pellet boilers. There’s a huge range of how automated the boilers are. When you think about what a boiler does, it can transport the fuel or not, it can ignite itself or not, and it can clean itself or not. Some boilers have all these things automated…—oh, and it can de-ash itself or not. The completely automated boilers have a truck that pneumatically blows pellets into a bin, and then the boiler pulls pellets out of the bin, either through an augur or a vacuum system. They all combust the pellets, but some of the boilers will turn themselves on and off; others, you do that manually. Some of the boilers clean themselves; others, you do it manually. And some pull the ashes right outside.

菲尔：我的猜测是颗粒锅炉的市场是您所说的：说：“我喜欢这个主意，但工作太多了。”我想，Pellet锅炉最感兴趣的是为您完成这项工作的大部分工作，但您仍然可以获得木材的优势。

帕特:这些都是相对较新的市场上,所以我们don’t have enough of a record to know which way they’re going to go. Coming up in the marketplace we have a boiler that is bulk-fed, so you don’t have to carry pellets into your basement; those are blown into a hopper in the basement. They’re transported from the hopper to the boiler automatically. Once a week, or once every other week, you’ll go down to the boiler and shake a little lever. It’ll take two minutes—actually, it will take five seconds. There’s a mechanism inside; you’re knocking the ash down. And once a month, maybe six weeks, you have to open the boiler and pull the ash out. That boiler costs about $7,000 less than a boiler that does those two things for you. So, that’s where I think the market is. Yeah, you can have it completely automated, and some people will want to. Or you can have a little bit of interaction, and save a bunch of money. For the last eight years we’ve been selling a really nice boiler that you have to bag feed, you have to de-ash, and you have to clean—and guess what, we didn’t sell that many of those.

菲尔：让我们介绍一下我们用木锅炉做的所有事情，因为我想并排看到这些东西。它是什么样子的？因此，您已经添加了一个料斗，但是您已经摆脱了我地下室里的实际木材。

Pat: It doesn’t look that much bigger than an oil boiler—it’s a little bigger…

Phil: The hopper is.

Pat: No, the boiler itself. You want to size the hopper for no more than four deliveries a year. A ton of pellets is 40 lb. per cubic foot. About 4 by 4 by 5 is what a ton is. So, a house that burns 900 gallons of oil would burn 8 tons of pellets. You wouldn’t want a hopper less than 2 tons; you’d probably want it closer to 4 tons.

克里斯：您全年都会得到一些补充。A truck drives up, takes out a hose much like an oil hose only much thicker—static lined so it doesn’t ignite any dust—hooks it up to a big fitting on your house, and then he just turns it on and blows pellets into the hopper. Does it whistle?

Pat: No, it hums.

菲尔：噪音怎么样？

Pat: Of the boilers? They’re much quieter than oil boilers. The fans are much more gentle.

克里斯：灰尘怎么样？我有这个料斗，卡车将把木屑颗粒吹入我的地下室。它与煤炭非常相似；它仅限于露天，对吗？

帕特：有各种各样的料斗。我们已经使用了金属料斗，我们使用了在现场建造的胶合板料斗，我们使用了布料。我们设计了几个料斗室，底部有一个预兆。料斗很酷，因为它们是为此目的而设计的，您只需要一个软管即可。您将颗粒吹进去，而料斗会散发出空气，但不要灰尘。像真空袋。

Phil: Does this have to sit in conditioned space?

PAT：不。我们刚刚设计了我们的前两个筒仓系统，它们坐在外面。我们从农业供应房来获得孤岛。

Phil: I see an architectural opportunity here.

Pat: We were talking about that for one of the jobs. I said, “We can build this building and make one of those silo rooms. It’s going to be really expensive, and you’ll have to build a building for it. Or you can just buy a hopper. 7,000 bucks and you’re done.” And they were like, “We don’t like the way it looks.”

Chris: Hire an architect, and we’ll make it look great!

Pat: Well, I suggested they tape pine needles to it. A lot of glue…

Chris: Like I said, hire an architect…

菲尔：松针？

Pat: Well, it was in the woods, to kind of blend in a little bit…

克里斯：锅炉应该在条件空间中吗？

Pat: We haven’t done a ton of these. We’ve done about two dozen of the old-school types and five of the fully automated types. So, we’ve designed our first direct heating system with the hopper outside and the boiler in a room all by itself. And it’ll be anti-freezed, and it’ll pipe heat underground. Most boilers can have anti-freeze in them; it depends on the heat exchanger. Modulating and condensing gas boilers don’t want to have too rich a mixture of antifreeze.

Chris: Is the quality of fuel with pellets a consistent thing?

Pat: The way to think about it is, it’s not the quality of the fuel, but a combination of the quality of the fuel and the appliance that’s burning it. The issues are going to be: Bad fuel creates a lot of ash; and pellets have a lot of minerals in them with a low melting point and can form clinkers, so the ash solidifies. They look like lunar rocks; they’re crazy. If you’re boiler is able to deal with those, it really doesn’t matter. It’s tricky, because I can only look at technology and ask myself how this is going to do for a decade…

克里斯：因为没有人可以打电话，因为你不会说德语。你会说德语吗？

帕特：不，我不。我有一个说德语的伴侣。

Voiceover：就是这样的一部分。下周收看更多绿色建筑师的休息室播客。快速提醒，我们的音乐是Perez Prado的“ Zelda的主题”。我们的观点和饮酒习惯并不一定反映了绿色建筑顾问。大家，感谢您的调整，并保持良好的工作。