So you purchased some land and you are wondering where and in which direction to place your home?
We currently know of three considerations which pretty much answer this question:
We sleep with our heads in the east and our feet in the west.
We’d like to benefit from passive-solar heat – which means most of our windows (and thermal mass considerations) will be facing south
We’d like to have a great view
The order they are in is not random – it reflects our priorities. It’s hard to enjoy a nice view from a cold house. It’s also hard to enjoy a nice view in a warm house unless we sleep well. So sleep, warmth and view is how it goes.
Once that is set it can be useful to get more specific about the actual position of the sun over the months and seasons of a year. You can then place the sun relative to other natural elements in the landscape (hills, trees,etc.) and then decide where is best to place windows to make the best of what sunlight is available.
One way to do this is to actually be on-site for a year and make measurements. When this is not possible there are solar calculators to do the trick for you.
To do this you will need a solar map calculator – a few of which are available online:
I think the easiest and friendliest calculator is at PVEducation – where you can easily shift the time of year to see the solar path change.
A simple and useful charting tool I found (so far) is SunPosition Calculator which has basic free functionality and extended paid options.
A more complex and elaborate tools can be found at SunEarthTools.
To use these tools you will need to find the latitude and longitude of your site location. You can do that here or just search the Internet as there are many freely available online options.
We want to have a really pleasantly warm house when it gets cold outside. Building with hemp insures that we enjoy a wonderfully insulated home. Now we need to deal with heat – which includes both environmental heating and water heating.
In typically built houses which tend to be cold when it gets cold outside it’s more a brute force challenge. With an ecological house it is actually more complicated because it’s easy to design a system that overheats the house. We still don’t have a clear picture or understanding of our heating needs – though we are working at it.
In the meantime I wanted to share with you some great resources that we are using to educate ourselves:
Stoves Online (UK) – it s great resource for learning about the different elements that make up a heating system with a very rich offering of solutions if you happen to live in the UK.
Boiler Stoves (UK) – seems like a sister website which specifically explains how boiler stoves work and can be incorporated into a smart and efficient heating system.
Radiant Design Institute – though not an appealing website has a lot of really well-grounded and useful information I believe can be very useful especially to do-it-yourselfers.
It’s been over a week that I’ve had the website for Modece Architects open in my browser. I really enjoyed the website – it feels like an authentically green site – one that actually walks the walk. Particularly I’ve browsed back and forth endlessly in the sustainable-construction gallery which has been quite an eye opener. For example …
This image hints at the potential of using quality timber framing together with hemp construction – which I was just wondering about…
or this image that demonstrates that loose hemp!!! can be used in floor insulation:
… or this image of a do-it-yourself solar panel:
… honestly, every picture in their gallery is like a magical doorway into knowledge.
But what really tickled my fancy was that as I was revisiting that must read book on hemp-lime construction I recommended a while back – I made the connection that the hand-drawn illustrations starting on page 31 were contributed by Ralph Carpenter of Modece Architects … and I am thinking “yeah, that’s the website I’ve got open in my browser” … so it seems that the world of hemp-lime construction is still a nice and intimate community 🙂 Great fun!!!
IMPORTANT: this note was added after the post was published but seemed important enough to be inserted at the beginning of the post. I am just now realizing that my perception of heating requirements are based on experience of poorly insulated homes. This is why I expect stoves to be lit numerous times a day. But, in a properly insulated home the need for heating should eb drastically reduced. If this is true – then all our elaborate plans to use stove-heating may be irrelevant – since the stoves may not be lit long enough to generate hot water. Having a super-energy-efficient home may lead to us to simpler, existing ready-made solutions. We don’t know, and we don’t know yet someone who knows … so for the time being it’s all up in the air.
Some weeks ago we described an imaginary-heating system and since then we’ve come across numerous resources and refined our understanding a bit.
I think there are two core ideas that shape and guide our understanding and wishes of a heating system:
Most of the time we can shower when hot water is available – though it’s comfortable we don’t really need hot water to be available on demand.
Enough direct heat is generated by our wood-stoves to indirectly supply most if not all of our heating needs.
So what we can say about our envisioned heating system?
It will be an integrated water-based system – the same systems is used to generated running hot water and water for a radiant heat system.
The system relies as little as possible on electricity – we would like to have a warm house and hot water even during a complete power-out (though it may run better when powered with electricity).
The system will include an indoor cold-water container that will bring the water to room temperature.
The system will include a central hot-water tank (not a boiler!) that supplies both the radiant heat water and flowing hot water to facuets and showers.
The primary source of heat will be classic Romanian-village-style terracotta wood stoves. We expect to have one or two primary stoves in the living-space and kitchen. We both work from home a lot and cook a lot so these stoves will already be working.
We would like to design and build the wood stoves to include an efficient coiled water pipe that is connected to the radiant heat water circuit and feeds back into the central hot-water tank.
We would like to install a on-demand gas water heater on the running water hot-water circuit as a backup in case the water in the hot-water tank is not yet hot enough.
Passivhaus is one of the terms out there in eco-green-sustaintable building land. It may look like its spelled wrong but that’s because its originally from Germany. It represents a very strict and high standard of energy efficiency in a building. It isn’t (yet) an official requirement or standard but it is gathering momentum as an unspoken standard.
There are three complementary core ideas behind the idea of a Passivhaus:
Complete and thorough thermal insulation of the house which prevents conductivity of heat from the inside-out or the outside-in.
Complete air-tightness which prevents exchange of heat through air leaks (windows, doors, pipes, chimneys … every opening needs to be sealed!).
An efficient ventilation system that both exchanges air (from the outside and the otherwise airtight house) and does so without losing heat.
This is one of those images that is better then a thousand words. The apartment building on the left is standard/traditional building while the apartment building on the right is built according to the Passivhaus standard. That’s the bottom line of Passivhaus – keeping the heat from escaping means you need to expend less energy to heat the inside.
Extreme!?
I have come across Passivhaus numerous times in recent weeks and my recurring personal impression is that it is too extreme:
It seems like more of an academic indulgence then a practical construction practice.
It’s objective and success is measured in a single number – the amount of energy needed to heat a square-meter of space.
It demands rigorous builing disciplines which require uncompromised excellence in construction.
It demands the use of specialized insulation materials which can be expensive (especially if you consider the ecological foot-print involved in manufacturing them).
It creates a house that demands constant attention, maintenance and proper use by its residents (every window opened and every hole drilled in the wall is a potential energy hazard).
All of which results in a delicately balanced system: if it isn’t absolutely sealed, perfectly ventilated by a carefully installed system and properly used it just won’t work. There is no room for error. This maybe OK in a scientific experiment but not so for life, nature and people.
In any case it doesn’t feel right for us: we have a limited budget, average construction capabilities, standard building materials, etc. We are going to do the best that we can with what we have. It’s an 80/20 kind of thing – where 20% of the effort takes you 80% of the way you need to go and it would take another 80% of effort to go the rest of the way. We’re aiming for a good middleground – pushing the limits of what we have – but that, by definition, is not enough to go for 100%. Passivhaus is uncompromising, but we live in a reality which demands compromise.
“A passivehouse is cost-effective when the combined capitalized costs (construction, including design and installed equipment, plus operating costs for 30 years) do not exceed those of an average new home.”
I am hesitant to relate to this statement as that may give it unwarranted legitimacy –Â cost is just too narrow a perspective to view ecological housing. But if I do meet it head on, as is, I would say that it sets its sights much too low. I hope to build a house where the combined capitalized costs are much lower then those of a new average home (whatever that is). I also hope to build a house who’s qualitative effects (both for us and others) far outway it’s economic effects.
Maybe Passivhaus is, for the time being, a high-end building experiment? Maybe in time it will spawn accessible, affordable and feasible techniques, solutions, technologies, practices … that can become a defacto standard that simply makes sense to follow? For now, it is out of touch with us and our needs.
Humidity
Having said all that exploring Passivhaus has brought to my attention a factor I had not taken into consideration in all of my energy research: Indoor Air Quality. I have been following a very basic intuition: “generate heat” in trying to solve a problem we’ve been having for many winters: “being cold”. Most of my attention has been on how to preserve and generate heat (space and water) effectively.
I had not given any thought to one of the central themes of Passivhaus: quality of air. Quality of air (assuming there is good ventilation) is strongly effected by humidity … and humidity effects the overal experience of temperature … cold is much colder when humidity is too low and heat is much hotter when humidity is too high. I have experienced the effects of humidity in warm and cold temperatures in Israel and I have seen it (as accumulated moisture and mildew) in almost all Romanian homes I have visited.
I don’t know yet enough about ventillation and humidity.
Hemp
One of the much praised qualities of hemp masonry is it’s breathability. It seems to have a natural tendency to absorb and expel unneeded moisture. I don’t yet have enough information on the overall effects of hemp on moisture, ventilation or quality of air indoors – but I do have a good feeling about the effects of hemp!
Resources
Following are some of the resources I came across and consumed in trying to understand Passivhaus:
We are spending a lot of time looking at potential energy solutions – solar, wind, hydro, geothermal … anything and everything. There’s a lot of knowledge to be acquired and there are a lot of companies looking to sell their products and solutions.
The one thing they all have going for them is a promise of a so called better day – super efficient solutions to basic needs, making better use of the environment, lowering carbon foot print and what not. It’s all very appealing … but our overall impression is that most of these technologies are not relevant for us.
Experimental
A lot of these technologies are still experimental – there simply has not not been enough experience with these systems to get a clear picture of what they can do, how well they can do it and for how long. If you factor in mind diversities such as climate, culture, lifestyle, natural resources … then the picture becomes even less clear and conclusive.
If you are considering such systems you are probably better off thinking of them as experiments rather then solutions. Experiments are a process of trial and error that may or may not lead to a workable solution. Make sure you have a capacity for experimentation – because no matter what kind of promises and guarantees you will hear from product manufacturers – there are more unknowns to their products then they care to admit.
Complexity
A key factor in any solution we consider is both it’s simplicity. The simpler the solution the less likely it is to break down and the easier (and less costly) it is to fix when it does happen to falter.
When the luxury of electric windows started appearing in cars they failed alot which was very bothersome (not being able to roll-up or down a car window) and terribly expensive to fix. It took somewhere between 10 and 20 years to reach a point where the simple mechanism of an electric window became reliable.
In addition, the last 10 or 20 years of production seem to have suffered a drop in quality. There was a time when a washing machine was engineered to last 20 or 30 years, now most machines falter after 4 or 5 years. New machines are also so complicated to fix that often it is cheaper to throw them away and get new ones instead of fixing them.
This meeting of complexity and experimental doesn’t invoke confidence.
Indulgent
Most of the technologies are prohibitively expensive. We can’t help but feel that they are a fashionable indulgence more then feasible, ecological, responsible solutions to energy challenges.
Our meeting with these technologies (as is the case with most of the other people we know in this context) takes place in the context of moving into a simple and sustainable lifestyle – where do-it-yourself replaces consumerism, where money is a limited resource and where finance is not welcome. The price entry barrier is so ridiculously high that these technologies are simple not relevant.
Availability
Alternative energy home/residential products seem to be widely available in the USA and some developed west-European countries. They are not easy to come by in Romania (and I’m guessing in many other places) where they can be of great value (i.e. a self-sustainable village home).
This is another sign to me that these technologies are still more of a fashion then actual feasible solutions. They are highly available for the rich to play around with (and feel they all green about themselve as they consume copious amounts of energy) rather then where they can be best leveraged.
Production Waste
Looking at a lof of these solutions makes me wonder about how much ecological waste was created when they were produced. This is an often overlooked aspect of ecological solutions – they may run efficiently and saved you a lot of money – but how much of an ecological foorprint did they leave behind them when they were manufactured?
Overall it feels to us that this is not a good time to get involved in most alternative energy technologies. Any temptation to actually use them are tempred by the lack of clarity, complexity, limited availability and prohibitive costs of such solutions.
We will be looking into technologies which are simple, affordable, well established and relatively predictable such as photovoltaic and hydro-electric solutions.
We will be re-examining every aspect of our lifestyle to see where we can consume less and make the best of what we do consume.
I came across this really useful website on alternative energy. It looks like it’s been gathering dust and it’s design is somewhat outdated but it’s information seems timeless. Whether you want to go about doing it yourself or to use commercial solutions – their website is a great resource of information – check out Other Power.
Through their website I found two other useful links:
The other is Bergey – a manufaturer of products and systems. Specifically their Packages pages provides tangible understanding of (a) the potentially high costs of commercial systems and (b) the relative costs of components that are needed to put together an entire working system.
Here is an example of a system that delivers: 400 – 1,500 Kilowatt-hours (kWh’s) per month (depending on wind resource), 24 hours to over a week of back-up power (depending on load and wind).
7.5 kW BWC Excel-R/48 w/VCS-10
$26,870
100ft. guyded latice tower kit
$14,145
Tower wiring kit
$1,615
DC Power Center, 9 circuit
$850
84 kWh, 5 String, Battery Bank
$15,000
7.2 kW Inverter system
$6,676
Total costs
$65,156
The most expensive elements are the turbine itself, the tower and the batteries. The price of the batteries was informative to me because they are needed regardless of how you generate electricity (wind, solar, hydro… ).
