Low Energy Housing , Net Zero Energy Homes , Stuff that makes me crazy
How zero is net zero…what’s not changing?
So there’s lots of excellent work and capacity building going on and Net Zero Energy and Low Energy and High Performance houses are being designed and built throughout North America. Innovation and forward thinking abound. It’s all very exciting. But there’s a place past which most builders, designers, and homeowners will not go: beyond low-flow plumbing fixtures, specifically toilets. Massive infrastructure has made it pretty convenient to not think about the consequences of flush toilets. Sure, there are problems with effluent and e.coli and we have to treat water severely before it can be classed as ‘clean’ once we flush it, but there are engineering solutions for that, and there’s lots of money tied up in that, and this system works just fine, thanks, with a few extra jolts of chlorine added every once in a while.
But really, no. There are big issues. This is not a good version of an open system. Piped water is a great convenience and a massive boon to public health, at the same time that it’s a disaster for the environment.
Water usage and access to potable water is in my mind a lot right now, with water rate hikes, and low-income households in Detroit having their water turned off due to one missed payment (yet 80% of the unpaid bills are corporate customers), and the looming potential of privatization of water resources. Tank Girl anyone?
Water shut-offs at the city scale, like what’s happening in Detroit (hey, kick ’em while they’re down, whydoncha?), are likely precursors to major health problems, to homes being made uninhabitable, and to state-sanctioned removal of children from their homes. How is that cost-effective? What are people going to do? Where are they going to go (in so many ways, where are they going to go), and how does the city expect to garner property taxes out of more derelict, abandoned houses? It’s a painful situation where solutions need to be found, and quickly, but this plays out quickly in my head as a worsening situation not an improving one, not even in the short run.
This article, by Lloyd Alter, managing editor of Treehugger, does a good job of dissecting problems with the North American approach to piped water and poop. I like his observation that the modern bathroom hasn’t changed much since 1910: small room, porcelain fixtures, line everything up in a row to use less pipe. Done.
Ya, except is this the best way to do it?
Critical analysis would indicate not: just from a health point of view, flushing a toilet sends reams of bacteria into the air. And sinks are right beside toilets. And toothbrushes are right beside sinks. Ew.
And there’s more: toilets are designed for sitting, we’re designed for squatting…ergonomics 101 have not been applied to the standard bathroom layout or fixture design. But we do have have an engineering solution.
But flushing is the big thing that circles back to my concerns about piped potable water usage and energy use and costs (not to mention the burden on aquifers and such): flush toilets result in millions of gallons of clean, potable (ie, drinkable) water contaminated, churned up and redistributed for your swimming pleasure. Ew. It wouldn’t be quite so bad if the blackwater (toilets) and greywater (pretty much everything else) were separately treated. Then at least the lightly contaminated greywater could be treated in a different manner that quite possibly would be less energy intensive, bringing down the overall amount of energy required to treat water (from Alter’s article: 10 bn litres of sewage/day in England and Wales requires ±6.3 GW hours of energy to treat, nearly 1% of daily electrical consumption for the two countries).
What if there were no blac
kwater? If there were no flushing…
Compost toilets have been around for a long time — I first read about them in my cherished 1981 first edition of ‘More Homes and Other Garbage: Designs for Self-sufficient Living‘. Clivus Multrum was then, and still is, the Cadillac of Composting Crappers.
It could be time to re-write Witold Rybczynski’s classic from the ’70s ‘Stop the Five Gallon Flush‘ (That book was out of McGill, it was brilliant, and yes, I have a copy), as ‘Stop the Flush’.
Except of course, people would be responsible for their own shit.
That could be awkward.
Or it could be a re-learning of how open systems work — you have an environment, there’s input from the environment, there’s throughput, and there’s output back into environment, feedback comes from the environment and allows for changes that allow for survival and growth.
THAT would be fine.
Deep Energy Retrofits , Energy Efficient Stuff , Indoor Air Quality , Stuff that makes me crazy
Damp basement season. It’s coming
What are you going to do about it? Hopefully not install an exhaust only system to pull more humid air into your humid basement.
Don’t. Do. It.
I’ve been discouraging these systems forever, here in Nova Scotia. They don’t reduce humidity levels in basements, but that’s what the marketing infers. What they do is exhaust the humid air from the basement while bringing in humid air from the outside. There is no way to reduce relative humidity levels and stop condensation without a) increasing the ambient air temperature so that it can carry more moisture while at the same time increasing the temperature of all exposed (or first condensing) surfaces or b) stripping moisture out of the ambient air (that’s what a dehumidifier does — oh, wait, that’s the market these exhaust only systems are muscling in on). In reality, the best way to deal with humid basements is to #1 Find the moisture source(s), and #2 Eliminate them. That’s the straight up, bottom line, end of story.
Moisture sources like open sumps are the problem — sealing this off before doing anything else will go a long way to reducing the moisture level in your basement or crawlspace. Note the white efflorescence on the wall — that’s salt crystals left behind from moisture migrating through the wall.
Open sumps, cracks in concrete that allow bulk water into the basement, these are pretty obvious sources. Less obvious sources include crappy drainage at the foundation, damaged or non-existent drainpipe leaders, high water tables.
Then there’s the fact that cooler surfaces cause moisture to condense out of warm, humid air. Concrete or masonry, present in most basements, are terrific first condensing surfaces. Insulating concrete and masonry can help to reduce the extent of condensation. But only if all moisture sources are dealt with so there’s trapping of more moisture in the basement…so back to #1 above.
Read this blog post by Allison Bailes at Energy Vanguard if you want more details about the pitfalls of exhaust-only systems and a fantastic in-depth explanation of why they won’t, don’t, can’t work in basements. Although he references New Orleans specifically, the physics that lead to problems with humid air and cold surfaces, along with the need to eliminate moisture sources in basements and crawlspaces are the same everywhere. The severity of the problem is related to the climate zone and the condition of the basement.
Oy vey.
We are so beyond the theoretical concept of energy-producing houses. The first generation of NZE builders are now at the dial-it-in phase. What worked, what didn’t work, how to improve performance…minimal thermal breaks, maximum thermal envelope, simplified and small mechanical systems.
Somehow I expected that an article pitched and purchased by the Smithsonian would have a little more oomph and research to it.
Energy Efficient Stuff , Stuff that makes me crazy
Sir, Ma’am: Step Away From the Foil Faced Bubble Wrap!
So Martin Holladay at Green Building Advisor blogged about foil faced bubble wrap last week. Will that stuff and the ridiculous claims around it in regards to insulation ever ever ever go away?
And here’s a recent 4-pager from NAIMA
I see that Allison Bailes at Energy Vanguard also blogged about it back in 201o.
And here’s a bunch of info I posted in October 2007. Note that even then, I couldn’t believe that it was **still** something that had such bandwidth. This was posted on the old Green Building Listserve…but the whole article is available as a pdf here.
There’s a good discussion going on in the LinkedIN RESNET BPI – Energy Audit & Home Performance Group, instigated by Chris Laumer-Giddens.
One comment sums it up: “The fact that Mr. Holladay felt compelled to write this article is troublesome because it just goes to show how many unqualified, willfully ignorant contractors are out there. Not only do these people offer their clients little return on their investment, it’s likely they diverge from code and protocol, causing property damage and potentially endangering lives.”
The stuff of nightmares…litigation and very unhappy householders.
More excellent discussion has come up today, courtesy Arlene Zavocki Stewart in regards to the issue of ‘effective’ R-values. R-value, U-factor = measurement of conduction. Building envelope materials all have properties that impact heat transfer via convection and radiation as well as conduction, but mere mortals using standard issue energy modelling software acceptable to home performance, DSM, and other incentive/funding programs, can only measure or model the conduction portion with any vigor. Engineers, physicists and fans of complex spreadsheet building (she raises her hand sheepishly) may be able to do otherwise, but it doesn’t count for your client if you can’t plug it into the modelling program and have it make sense with what’s already being calculated. I have bumped into this challenge in terms of modelling thermal mass for cold climate passive solar design, but it’s the same issue: how much heat gain does a material or assembly absorb or reflect from a radiant source, and how much does that contribute to the heating or cooling regime of the building?
Arlene brings a great point to the discussion: “Codes allow ‘cutting edge’ products but our ways of measurement and communication on their features often can’t be quantified in existing conventions. Developing accurate ones is very expensive and takes years for widespread adoption, a funding line item that investors just don’t seem to account for.”
In the meantime, we have ‘snake foil’ salespeople out there, talking up effective R-values that defy all the laws of thermodynamics. I will stop short of banging my head against the wall now.
OK, the time has come to debunk the flowerpot space heater idea. People are going to die. They will be cold, asphyxiated or burned to death.
The flowerpot + tealight heater wonder of the world don’t ever use any other heat source article has been coming across my feed for weeks now, with people gaga over the cheap and amazing heating source. It’s not. Four tealights produce about 800 Btu/hr. To put this in perspective, one 100W incandescent bulb produces 340 Btu/hr, 90% of which is heat, so if you are burning two of those bad boys in a room, you are providing 600 or so Btus to to space.
The claim on the video is 8p (14¢ CAD)/day. However, Presidents Choice 8 hr tealights cost 16¢ each ($8/bag of 50, tax not included). So the cost for 800 Btus of heat = 64¢ + HST for 8 hours. If you were to compare that to burning 2 – 100W and 1 – 50W lightbulb over 8 hours, in Nova Scotia, with electricity charges hovering around $0.13CAD/kWh, you would be shelling out a total of $0.26 + proportion of base charge etc. Not to mention the fact that you would have the non-energy benefit of enough light to read by anywhere in the room.
It’s kind of a moot point since incandescents are now banned in Canada (but that’s another rant for another day).
Let’s look at other claims, or misrepresented/misinterpreted statements:
The flowerpot does not act as a radiant heat source (that’s the candles), nor does it amplify the heat source (that’s impossible), it only acts to concentrate the heat produced by the candles in a very constricted area, before it dissipates to the rest of the cooler air in the room (yes, that is the convective aspect of the construction). Not only does the flowerpot add nothing to the available heat, it does not store any of the heat for any appreciable length of time. It is not ‘like’ a thermal mass heater — it is only similar in concept. A masonry heater typically has 5+ tons of masonry absorbing then radiating heat — not your average clay pot or two — and a fire box that essentially recreates the conditions of a blast furnace to heat the mass. Clay has a specific heat capacity just slightly higher than air. To serve as useful thermal mass, the clay would have to be much thicker than a flower pot and preferably mortared into a large surface that is buffered on at least one side by another mass that minimizes heat loss to lower air temperatures and colder surfaces.
Let’s look at how the tealight-flowerpot gadget stacks up, performance-wise, against a standard-issue radiant-source room heater (to compare apples to apples), because that’s what it’s replacing. Room heaters that work off radiant heat sources, such as oil-filled electric units are cost-effective (and healthier), as mineral oil has a specific heat capacity that is more than 1.5 times that of air. These room heaters use electric elements to heat and circulate mineral oil in a series of fins that then radiate heat to the room via an expanded surface area.
A standard 2kW room heater can provide 10K Btu/hr. To match this amount of heat would require 13 4-candle teapots. That’s 52 candles that last for 8 hours. So let’s do the math. First let’s look at purchase prices and value-for-money:
I bought such a room heater for $80 (+HST) last month at Canadian Tire…that means it’s worth 10 bags of tealights, which will give me heat for 80 hours, and then I have to replenish my supply. Its cold in Nova Scotia for way longer than 80 hours. So lets say I buy 20 bags of tealights in total, which will keep me warm for 160 hours. Still not adequate for winter. Even if I’m willing to put on six sweaters, four pairs of socks, a toque and chop my candle-flower pot heating system in half so that I get 320 heating hours out of it, I’m still nowhere close to adequately providing absolute minimal comfort levels. Now I’ve paid out $160. and I’m not comfortable and I don’t have enough heat for the winter, and I’m subjecting myself to crappy indoor air quality, meaning I have to fill my asthma prescription twice this winter instead of once. Oh wait. I haven’t accounted for the cost of the flower pots. Assuming I don’t have them handy, that will add some more cost and what if I can’t find them in the off season?
Well, let’s say I’ve got the flowerpots on hand so we don’t have to factor them in. But the asthma prescription is $30 a shot.
So I bought the radiant heater for $80. If I use it at it’s full 2kW heating capacity, providing me 10k Btu/hr every hour, I can use it for 423 hours before I hit $110 (the second delivery of 10 bags of 50 candles + my asthma prescription. And I’ve been toasty (possibly overtoasty) for each of 423 of those hours. And I haven’t had a single poor indoor air quality-induced asthma attack or asphyxiated any pet birds or burned down the house.
PS. In the original video, the premise was the heat was provided by one flowerpot thingy (producing 260 Btu/hr) and the computer running (producing 1365 Btu/hr). The flowerpot thingy is not heating the room.
PPS. Regardless of how big your candle is, it will still ONLY PROVIDE 260Btu/hr.
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