You can do this too without changing your existing home or building a new one. I buried pipes outside and pull in cool air during the summer. 2 fans and a cheap thermostat use under 100W. The natural earth temperature at my depth is 59F when the air temp outside is over 95F. I can boost the cooling by running outdoor fans in the winter, pushing freezing air into the ground, lowering the temp another 10F, so the air cooling during the summer is very nice. This simple system was $400 in materials, uses under 1kW per day and pushes 250cfm of cold air.
@@emeraldcoastgardensfl7323 Your location may be easiest to build in due to the high sand content. The cooler soil will help condense that moist air and drain it off too. I guess the main thing to consider is how big is the space you're cooling. My example is under 1100sq ft and well insulated. Larger and thinner buildings will require more air flow, thus either stronger fans (or more of them) and/or larger piping system to capture the cold.
How deep did you go? I would love to do that in my house however I have an underground spring 1 meter deep to the NW of my lot that is directed through a French drain to the street storm system.
@@rodholden1974 to keep the temperature in the home steady. The ground temperature stays at a moderate temperature compared to the air temperature. You sink the house to kind of capture the temperature of the ground and heat or cool, according to the season.
When we bought our house, the first thing that I noticed was the basement had space for an office. I put my office down there and this summer, we’ve barely had the AC turn on. The basement produces so much cold air that I leave the fan on 24/7 and just pump the cold air upstairs. We got a heat pump last autumn and that changed the game too. We got rid of the Oil, ran the thermostat 6° hotter than we did the year before, and still saved USD 1000 Compared to the year before
The part that really got me was near the end, "But the reality is there was a lot of money thrown at this building to make its energy performance this good..." If the house costs an extra $100k, but only saves 2k per year in heating/cooling, you would have to use the building for 50 years to break even. Most people / places can't afford a significantly larger up front payment when it will take decades just to break even. If you want people to implement more environmentally friendly construction, you need to provide enough benefits to offset the increased cost, and this one won't cut it for most people.
School buildings are often *_used_* for more than 50 years, so "throwing money" at passive efficiency measures and high-quality materials is well worthwhile. My local school district recently replaced the high school and specified a fossil fuel heating system - cheaper to install, but extremely expensive over the next 60 years (arbitrary service life of the school.)
The "volcano" of the building uses similar principles to the stereotypical African mud hut/rural home. Conical thatched roof to maximise the stack effect plus the permeable thatch to help the heat dissipate easily without needing to compromise on weather proofing. For the earth sheltering, some people "sink" their buildings 1-2 standard step heights (
Combining traditional architectural designs developed over centuries to keep buildings cool is something that should be done much more. I'm sure there's good ideas from all over the hotter parts of the world that could be used for buildings in e.g. the hotter parts of the US. Could have been done for a long time already, but instead they built homes adapted for temperate climates and blasted AC cooling most of the year. All because of a "those aren't white people ideas" mindset, basically.
This is true of traditional Javanese joglo houses as well. Houses traditionally face the south where cool winds can enter the house and be shaded from the Sun that is in the North (we are in the Southern Hemisphere) Then the walls have gaps near the ceiling so all the hot air can rise to the top of the "volcano" roof and cool the building down
Using pumicecrete as a building material uses a fraction the time and money and has a good R value and last forever Using a building material that comes out of the belly of a volcano is a good building material Take care Ray
As someone mentioned, what about condensation in the air pipe? Bacteria, mold? It does have an access hole, and condensation can drain down, but I assume it's pretty hard to inspect and clean it. Do you have any long term data about earth air tunnels in similar climate? Like continental Europe?
The video mentions a slight slope in the pipe with a means for disposing of accumulated condensation, and a manhole for maintenance at the low point of the system. A 200mm (8 inches for Americans) pipe is big enough to be cleaned by any duct-cleaning service.
This is all under the umbrella of passive solar design. A very interesting and under utilized strategy in architecture, IMO. I believe it should be mandatory on all new builds. People in the comments asking about humid locations and other scenarios, there are passive solar improvements to be had in those areas, as well.
Wow, I've been thinking about this system for a few years and wondered if anyone had done it already!! Brilliant video Sara. Can you expand in the benefits of sinking the building into the earth "to the height of a school desk"
This is an excellent description of passive Heating and Cooling. The application to Mobil Homes might provide some practical assistance in solving World energy issues. The USA has a considerable number of Wobbly Box Homes that could benefit from the technology.
uh. I grew up in South Alabama, we've had passive cooling systems for a few hundred years. There is one home in South Florida that keeps the whole building well temperature regulated by using bimetallic springs (huge ones) to actuate wood louvers inside the hollow walls to keep it around 72F year round. Awesome design.
Love this. We are restoring a 100 year old school building designed in Canada using sun to do passive heating and all lighting and cooling using zero power via its special design. Today schools are boxes and don't use this design. Cheaper building strategy to sell to Governments then waste money afterwards to heat and light them. Stupid Governments getting more stupid or are corrupt .... both?
This past January (2024), 98 schools in the San Antonio Independent School District closed after 70% of them had some degree of heating system failure!
Passive solar is practical, efficient cooling/heating but not popular because it is not offered. Change is challenging. Established trades tend to be conservative, ignoring experiment. That's why we the consumer should do our own research, ask a lot of questions, carefully evaluate the answers, and not rely on "experts" who tend to only recommend what is convenient for them. The more you read, listen, investigate new ideas, the better your planning, your life. It's only logical.
130 KWh/sq meter? Seems pretty high. My current apartment is using about 42 KWh/sq m/day... Efficiencies vary, and this is a nicer, newer, more efficient building. Perhaps she's referring to buildings built 50 years ago, etc.. Either way, the point that if we build with efficiency in mind, and build long lasting buildings, we can save both energy and building waste over time. This is very similar to Earthships from Michael Reynolds out of Taos, NM. His philosophy is simple: Architects are the ones that can save this planet, by simply using more intelligent designs. Bravo Sara! We need more of this!
I get the concept. I just have serious concerns about maintenance and upkeep. (Mold, fungus vermin, condensate) That's a lot of buried ductwork to keep clean.
That volcano-shape roof is like traditional Joglo roof in Java island. Joglo roof has been used for hundreds of years back as the construction was depicted in the Borobudur temple relief carvings circa 700 AD. The function is the same, it draws the heat up the roof and circulates it outside. That Joglo roof can be 10-12 metres high, with thatched roofing or pottery tiled roofing. The Dutch East Indies houses also applied the same kind of roof, usually very high hip roof with no attic.
Very interesting video! Maybe a more in depth video of installation details, pro and cons of the Canadian tunnel for various situations could be interesting :).
There are good ideas here, but I'm a cheapskate! Still, the design can be done sustainably, for not a lot of money, and be fire resistant. Thank you for sharing your video!
Well, I'll give you more info and maybe you get interested... Rent an excavator with operator and dig the trench, lay down the pipes, I heard perforated helps the condensation go down into the dirt, and use a 12v computer fan to pull air from the pipes into the building. More pipes is better. Two 4" pipes is better than one 8" pipe. The longer and deeper the better. Minimum 4' deep by 50' long. Depends on soil type too, wet clays are best, dry sands and gavel the worst, you're looking for density of material surrounding the pipes for better temperature transmission. Also, where the hot air exits from the building is essential. High windows, and you can even have a solar chimney, look that up. The idea is to establish convection. I've even been thinking a cob structure to house the inlets would mean the air going in is even cooler, plus you protect the inlets from water splashing from rains and it adds a stealth factor to the system. I've also heard of planting aromatic herbs and plants near the inlets to get more than just cool air inside the building.
Nice explanation of the building. However, a point to note: Hot air itself doesn't evaporate, as evaporation is a process where a liquid turns into a gas. Hot air can contribute to the evaporation of liquids. When air is heated, it can hold more moisture, which increases the rate of evaporation for any liquid present. This is why hot, dry environments can cause water to evaporate quickly. In summary, while hot air can't evaporate, it can significantly enhance the evaporation process of liquids. Keep such content coming.
@@iwanabana I understand the RU-vid algorithm prefers corrections from some but not for others-just joking! Waiting for the next great video from this channel.
I'm very very interested in this topic and I would really like to learn more! For instance, regarding the air tunnel, it would be nice to know more details such as a correlation between the length of the pipe needed and the amount of cubic space that you want to preheat. I must say that these 25-50m with 20cm pipe doesn't really sound enough for a whole kindergarten? Are you sure that is correct? Also, condensation seems as a main issue for me. It's quite easy for mold to grow in those pipes even though the slope will surely get rid of the most of the condensated water. Any more info on that? I would have many more questions but well, these two are enough for now 🙂 Thank you for interesting and informative video!
I get that this building is expensive but these tricks can be used with less expensive materials, right? And you can build - as in this example - schools and post and offices and government buildings this way where people are the most during the day - helps already a lot. Muchmuchmuch more architects should at least think about it and incorporate such passive elements (according to the needs of a building if course). I love it and thank you for sharing.
You need to be far closer to a person to contract Covid. You’d have to cough from below the rain deflectors, upward into the mesh and filter, have it travel a long distance through a pipe, through more filters and into the building. Even if it were just a basic tube drawing air, the moist droplets from the cough would struggle to stay suspended in the air the entire length of the pipe
@@calvin2032 That's not true, the Covid virus is a tough bugger that can survive for days on solid surfaces, and float around in the air. I'm thinking you want to support the design more than you want to deal with inconvenient facts. Even so though, past Covid, what other air-pollutants or toxics can be introduced by air-vent? I think that is a reasonable question. Similar to the Legionaire's disease that can from air conditioning equipment. And what is the role of heat exchangers in conditioning air?
Thank you! 🙏🏽 yes, of course - sunrooms, trombe walls, direct solar gains through windows and double façades are good examples! I’m hoping to cover all of them in the next videos! ☺️
i live in the same climate and would ölove to incorporate this in my future home, i've seen so many cool videos on those air tunnels and how they work! they're apparently way more common in very hot climates where they built entire towers as air catchers! triple pane windows are just the new standard for european countries in this climate tho, they're nothing unusual or overly expensive generally
The last several years have seen some severe summer heatwaves in Europe. Cooling is definitely a factor now. More generally, good design that lowers your energy consumption is a good thing.
Here in Europe, and in much of the rest of the world, far too many residential and workplace buildings are being designed and built to the lowest budget or bid, putting speed and build profit today ahead of running costs and comfort tomorrow. Except for small experimental projects such as this and private commissions, it’s difficult to see these kind of methods and expenditure becoming commonplace without a significant sea-change somewhere.
the earth tube might be not in use in the coldest days. i wonder how they would deal with condensation inside the tube and how they prevent molds growing!
Yes that'a a good point - sloping the tunnel helps to get rid of any condensation. To prevent mould, it needs a constant airflow. Most tunnels have fans to allow this.
@@goglebert Perhaps a diverter flap to send cold air back outside. The principle behind the earth tunnel in winter is that the cold air absorbs some of the latent heat in the soil at 2 metres.
Take a look into radiative cooling (paint). That together with a traditional dome I think can be a good solution without increasing the budget too much. Also the buildings don’t need to be air tight what modern solutions often ask for.
Radiative cooling paint should only be used in places that are warm to hot the huge majority of the year. If you have anything remotely resembling a winter and use heating during same, then R.C. paint is not a good idea. That is, unless you are using it for isolated systems that can be disconnected. For example, using R.C. paint to cool some heat pipes that are piped into the home, but which can be removed in the winter.
I guess 2 elements affect that. The seasonal “balancing” by taking heat in the winter to adding heat in the summer from the pipes surrounding soil. And the relative shallowness might enable sufficient interaction with the top layer and air to exchange heat. One could add a heatpump to balance out any net results, requiring only a relatively small amount of power to do.
Do you think this type of implementation can be beneficial in tropical areas in the Caribbean, where cooling is the need? If you do, can you explain how this system will achieve cooler temperatures such that A/C is not required or at a minimum significantly reduced?
A big part of cooling in high humidity areas is removing some to a lot of the moisture in the air, which modern AC systems do well, but none of these passive systems do. There are ways to design passive dehumidification, but they require definite work to maintain. For example, you can put a large, large surface area container with an open top near a window inside a home. Insulate the container very well. Put A LOT of calcium chloride into the container. Put a home made "heat pipe" into the calcium chloride and via an insulated window insert, vent that heat pipe to outside (the part that is inside, needs to be well insulated). Insulate the top of the container with breathable insulation. The calcium chloride will absorb moisture from the air, but as it does, it will heat up (this is why you insulate the container and the part of the heat pipe inside). The heat pipe transfers the heat generated in the calcium chloride to the outside. The problem is, eventually the calcium chloride will become so saturated with water/moisture that it will no longer absorb any more, so you will need to bring it outside and use Solar heating to dry it. You'll want at least two separate amounts of calcium chloride so that you can have it continually running while one pile is being "regenerated" outside by solar heat.
How about cost effectiveness in mid-run? Standard and mechanical systems are easy to include and cheap. If people have to reduce energy usage, it has to reduce their bills enough to allow for higher up-front cost. Which of those passive techniques are definitely a saving for the first 10 years including installation cost?
So the building benefits from cool summers and mild winters, combined with the passive elements it can use up to 88% less energy than a similar building somewhere else, so this is an extreme outlier example. I'd be more interested in seeing a building like this built in the desert southwest of the United States or somewhere in the Middle East or Africa. That would be a good comparison against similar structures in those regions.
One concern I see is radon gas issues with this design. Exposure to it in areas that are not continually swept by airflow will be a real issue. And yes, I see the flow from the "volcano" but with furniture placement and corners, the flow doesn't necessarily get there.
That is a legit concern! I presume a radon survey is part of the multitude of surveys that need doing before construction starts - as for the ventilation, hot air naturally rises but also is pushed by cool air 👍🏽
Underground fresh air inlets have been tried and found to produce very poor damp air in practice. Schools should use MVHR to control CO2 and save energy.
The air inlet piping is 200mm in diameter but what length does it have to be to be effective. I understand the volcano, hot air rises and as it exit it pulls air from the cooled air from the underground inlet. But as winter cold air sinks, what is the dynamic that utilizes the inlet pipes. It seems there is nothing to pull air into the inlet, except maybe mechanical devices.
I've noticed a lot (all?) of these eco friendly buildings are built for either dry or temperate climates. Is there an eco friendly building for humid climates that get very hot and cold?
Is this still a viable option in areas where radon gas is an issue. Cracks or underground leaks in the Canadian well could introduce radon gas into the building. It seems that constant monitoring would be necessary in radon gas prone areas.
@@SaraSaadouni_TAC 10-4 👍. I’ve wanted to build a workshop that utilizes solar chimneys and what I know now to be called Canadian wells. So when I saw this video, I had to watch.
3:14 - "They also buried the building by about the same height as the school desks, making the window sill an extended workspace." 0.5 meters is an awfully low desk. As can be seen in the images just afterwards, it's more like the height of a chair seat. They're not extended workspaces, unless you're sitting on the floor.
Is the roof design to move air up and out called a toroidal design? I’ve heard this term for magnetic cores but also heard the term used when describing air movement in a very long Japanese airport. Though it wasn’t a round airport. Hum…
How does this ventilation affect indoor CO2 levels? Typically, schools have very bad ventilation and very high CO2 levels, substantially reducing the ability to concentrate and learn. Did they do CO2 measurements? Most of the time, authorities are incompetent in this regard and don’t care.
That's a really good point - I couldn't find any data on this but I presume this is supported by mechanical ventilation with heat recovery. I don't see how else it could be done.
What about the inclusion of awnings on south-facing windows (in the northern hemisphere) so that in the summer, the sun does not shine directly into inside space?
I'd be really impressed is someone could design a Passivhaus for hot climates like Phoenix, Arizona because hot city dwelling is in our near future, not cold, wet places.
Look at Middle Eastern designs, specifically Iran/Persian designs with Badgirs. But the biggest problem in cities is not enough trees / grass / green roofs
You're not wrong but I would think flooding is doing to mess things up regardless but yeah, it would be worse unless it has good protection just like you would in a basement.
@@Sensei_BigJoe flooding isn’t going to mess things up ‘regardless’ - in areas prone to flooding, you build on higher ground and/or put the main building up on stilts. An extreme example of this is on coastlines around the world.
My only comment is, please add some historical context. Nothing you describe is new yet someone discovering it for the first time will think that the Dutch architects invented all of this on their own. The "volcano" has been in use in Iran for over 3000 years. They call them Badgirs and they in turn were inspired by termite mounds which now we know are incredibly efficient at maintaining a constant, livable interior temerapture. Meanwhile the first attempts at harnessing geothermal energy go back to the 1810s in Tuscany. Later this evolved to using heat pumps for both heating and cooling. That technology was commercialised in the 1940s and there was a big push in Scandinavia and Germany in the on 1970s to convert homes and buildings to this kind of semi-passive temperature management. Giving credit and showing context does not detract from your videos. It makes them more interesting. Same can be said about your warm climate video where basically the 3 different techniques used are all vernacular, indigenous techniques, thousands of years old.
May I recommend that at 0:07 in the diagram you change the word "isolation" with insulation so it makes sense. There is no "Isolation" in construction however insulation is used for temperature and sound control. Great presentation.
This is really what I feel architecture is about - functionality. We're going to need more solutions like this as our climate becomes more extreme and unpredictable.
These aren't a problem, I assume, since these like warmer temperatures like in warmwater pipes. BUT what about mold? The Eastgate Centre implements similar strategies, but it is lokated in a mostly dry region, and buffers not only temperature but also humidity.
Update: Apparently the air intake filters as well as the condensation drain are supposed to minimize the risk of mold growth. Regular inspections and cleaning are still advised. These cooling solutions are still not recommended for hot and humid environments (as shown in the video). The risk of radon entering the tubes is to be considered as well 😅 For my climate I would prefer a heatpump with ground-pipes for cooling and heating, instead of directly using air.
@@mike_w-tw6jdnot through the system, by the system. The outdoor unit was growing legionella in its water supply, and that was traveling down the outside of the building to the entrance of the hotel. It was never spread through the conditioned air.
@4:13 Belgium and the Netherlands always had summers in which it can get really hot. This is normal for that latitude all over the world. There is no need to bring climate change into this.
