Air conditioning with wind, sun and water: Ben Bronsema at TEDxDelft

Air conditioning with wind, sun and water: Ben Bronsema at TEDxDelft


Translator: Els De Keyser
Reviewer: Ariana Bleau Lugo Ladies and gentlemen, the buildings
you see here are very different. There is a town hall,
there is a big ministry building, there is an airport terminal,
there is a head office of a big bank and a small bank, and an office
of a broadcasting company and also two old buildings
from the last century, a museum in The Hague and the head office of an important
Dutch trading company from the former century. These buildings were built in the 20’s
and the 30’s of the last century. Well, these are very different buildings and yet they have one thing in common: the airconditioning systems in these buildings
were designed by me and by my staff. (Laughter) Everybody can talk about airconditioning but few have ever seen
the heart of an air-conditioning. And what you see here on this slide is the very heart
of an airconditioning plant: huge air handling units
which cool and dry your air or heat it up and humidify it. Well, this has always been
important work for me. This was my joy, this was
my passion and my life, to design this kind of things. Ordinary people
are not allowed to go in there. And architects also
don’t like those systems. Architects dislike airconditioning, in fact. It costs a lot of space. They hate the pipes and the ducts. They hide them very carefully above the false
ceilings and in insulating shafts. And at last, airconditioning
costs a lot of money. It has to be funded
from the construction budget, and that’s their budget. Then next, do people like airconditioning? Well, they generally do not. They hate the noise of the fans, the draft of the cold air
that is coming into them, they don’t like the air quality, they think the inside air quality is not
as good as the outside air quality. They complain about dry air. And, well, energy consumption
of air conditioning is rather high. So that’s also not so very good
for air conditioning. So having a relationship with architects
that is a love-and-hate relation, and customers that do not like my products, you can imagine that I had
a very hard and difficult life. (Laughter) So, should I have given up
or is there a solution to this problem? Well, can we learn from nature? What you see here
is a termite hill. I’ve seen lots of termite hills
in Africa, in Kenya. They are very large buildings
they build for themselves. Inside that building, that mound, they grow a fungus. The fungus is
their primary food source. The fungus grows best
at a temperature of 30°C. So the temperature in the mound
has to be kept at 30°C, while at the outside, it’s 50° in daytime
and the sun is shining on the hill, and at night time, the temperature
can go down to about zero. So, can we learn from some —
could we design a building like those termites do? Well, we don’t know for sure, but I think termites do not split up
the design of these mounds and architecture [and] engineering.
They build it together. (Laughter)
(Chuckles) I say: as far as we know!
(Chuckles) (Applause) And I think termites are very satisfied with the endoclimate in their buildings. So could we imitate this,
the way termites do this? It’s called the biomimicry principle. Could we learn from them
and build a building in reality? Could we make buildings
in the human world as a machine
for natural air conditioning? Then I come to the words architect
and engineer – different minds. Architects are artistic,
intuitive and creative and engineers logical,
rational and well, I must say that architects sometimes
have very fantastic ideas but they leave the quality
of the endoclimate to the engineer. The engineer is always responsible. So, different minds. I have learned the mind
of the architect rather well during my career. About 20 years ago I was
appointed as a guest lecturer at Delft University,
at the faculty of architecture and I got to know the minds
of architects even better. And then I got a new idea. Can we build a building
with natural air conditioning in the way termites do it? How do the termites do it? Well, they very carefully open and close vents that let warm air out and let cool air in, and opposite. Could we do that in the same way
as the termites do it? And could we, by doing so,
have natural air conditioning, avoiding fans, could we, by doing so,
probably, maybe, hopefully, make a zero energy building and a building where the endoclimate is more like the outdoor climate
and people are more satisfied with it? Well, this was the idea. On a morning, I awoke,
during a holiday, and I said: well,
but what’s the title for it? What about Earth, Wind and Fire? That was the working title
for this investigation. (Laughter) I wrote a research proposal on that. And I applied for funding
from the Dutch government. Well, the Dutch government
took their time — about two years — (Laughter) but at last, I got
about a million of euros. That’s a lot of money.
The good old times, you can say. It is tax money. So you all contributed
to my research. Thank you very much.
(Laughter) (Applause) So when I got the funding for my research,
the research could start. It started in the early summer of 2007. My wife, Ilona, was recovering
from major surgery after chemotherapy. About 20% of the women
survive ovarian cancer. I was convinced that
she would belong to that 20%. Then in a week in November
came the message from the hospital that the cancer was back
and there was no more hope for her. I was a caregiver, so
I had to divide my time between Earth, Wind and Fire
and Ilona. But you can understand
that that was a difficult task. And at the end of the year,
my inspiration and ambition had gone so much that I thought: well, I’d better give up Earth, Wind and Fire, forget about that and
concentrate on my wife. But she didn’t agree with me. She said, “Ben, your work, your job has always been your passion
and your life, your joy, so go on with that. And when I’m no longer here, you still have a wonderful
purpose in your life. And that little voice, I still
hear it after so many years. So she died in February 2008. For a couple of months, I did nothing
at Earth Wind and Fire, but then, slowly, I restarted. (Ramses Shaffy singing:) Sing, fight,
cry, pray, laugh, work and admire. (Applause) This is the title page of my thesis, stating that singing, fighting, crying,
praying, laughing and working, I restarted the research and was more and more
surprised by the results. As a principal investigator I put together a team of researchers. Scientists of the University of Delft
and the University of Eindhoven. A fantastic combination
of old and young, of trained intuition —
that’s me, of course — (Laughter) and open minds —
that’s the researchers. Also practical experience,
but also scientific expertise. There was a fantastic team
to do this work. You see a picture here. It’s part of my research team
and also one of my promotors. We also had a project advisory team of people from the building industry. Once or two times a year we came together and they said what they thought
about the progress of the research. Well, this was the idea:
Earth, Wind and Fire. What you see here, is a cross-section
of an office building. The wind comes from the left in this case, but it’s wind direction independent, so it’s not important to place the building
in the wind direction, but there are overhangs at roof level and the wind blowing to the facade is caught by the overhangs
and is entering the building. Part of the wind is used
for air conditioning of the building, and part of it is used for energy production by wind turbines
that are not on this picture. At the left side,
you see the climate cascade where the fresh air enters. At the top of the climate cascade cold water is sprayed,
water of 13° C That cold water cools the air in summer and preheats the air in winter. The temperature of 13° C, we can get that
from cold from the soil. The soil is about 11 to 12° C, so we don’t need chillers, we can get
the cold from the soil to cool the air. Then the air is cooled, for instance, in summer from 28 degrees outside
to 18 degrees — about 10 degrees,
we can cool that. At the top of the climate cascade,
the water is sprayed. At the foot of the climate cascade,
pressure is built up. We need some pressure
to distribute the air into the building. Because of the weight difference
between the water air mixture inside the climate cascade and the surrounding, there is a negative thermal draught, so we have positive pressure at the foot. At the other side of the building, we have the solar chimney. The sun shines into the chimney, the air is heated up, is rising, it’s thermal draught, and at the foot
of the solar chimney, there’s an underpressure. That underpressure
exhausts the fresh air that is distributed
by the climate cascade. At the top of the solar chimney, we have a heat recovery system. It would be a pity, of course,
to leave all the energy that’s in the air. It’s not only the solar energy but also all the energy
that’s produced in the building. the heat from lighting, from people,
from computers and so on. All that heat is recovered by water, that water is heated and stored
into the soil beneath the building. We can use that in winter
to heat the building. Then the air is going up
through what is called a venturi ejector. This room is like a venturi. When wind blows through the roof,
the wind speed is accelerated and there is an underpressure
in the heart of the roof. By that underpressure, the wind, the air
is removed from the building. This works all naturally. We only need one small pump to pump the water up
to the sprayers. That was the idea. I concocted it myself
in a very coarse way. But it has to be calculated, of course. So the scientists
from Eindhoven and Delft made very sophisticated
computer models. But what is the value
of a computer model? It always needs to be tested. So the next step was that we built physical models, physical mock-ups. In those mock-ups,
we did all the measurements and based on those measurements
in the physical mock-ups, we could validate the computer models. So we have very reliable
computer models now. It turned out to be really good. We have very reliable models. It’s amazing that you can
make a CFD simulation of hundreds of thousands
of water droplets — what is the cooling effect? —
but it can be done, and it was really fantastic to do that. You see the tester here,
a mock-up of the solar chimney. It’s eleven meters high
and two meters wide. For one year,
many points were measured: the solar radiation, but also
the temperatures inside the solar chimney, the air velocities and so on,
and on the basis of all those measurements we could validate and
verify the computer models. And it turns out that we have
a reliable computer model for that. We did not only build a test mock-up
for the solar chimney, but also for the climate cascade
and for the ventec roof which is tested in the wind tunnel. Well, the question is: will people
like natural air conditioning? Well, most probably, yes! There’s no noise,
there’s no draft, the air is not so cold,
it’s about 18° C, there is outdoor air quality,
the best quality you can have, there’s no dry air
and the system uses very little energy. But of course the building itself consumes energy, because of the lighting
and so on, and the computers. So we need to provide for the energy consumption
of the building itself. So the next idea was to produce the energy
for the building in the building itself. We designed a power plant on a roof, a power plant using wind and using sun to produce energy — sun by PV roofing
and wind by wind turbines. This is a picture of such a power roof. It’s an energy power plant for the building. You see the wind turbines
in the pressure room and you see the ventec roof and a wind turbine can be
situated in there as well. In the best case, we can produce
all the energy we need in the building. This is an exploded view of the roof. Here is the entrance
of the climate cascade. You see the turbines running. Again. Then at last — the idea
of Earth, Wind and Fire was to apply it in newly designed buildings. That can be done:
you can design a building so that it is ideally suited
for the Earth, Wind and Fire concept, but there is no big building production
at the moment, so I did a test, a virtual case study on an existing building in Amsterdam. This is the new view of the building. This is the south facade. We made a complete
solar facade on the south. You see the roof and the overhangs
and the ventec roof. Well, it can be done. We calculated — we tested, of course,
but only virtually — that by the Earth, Wind and Fire concept you can reduce the energy
consumption of the air conditioning by about 40-60%,
and the remaining energy we need, can be produced
in the power plant on the roof; purely with nature. So I can say that Earth, Wind and Fire
is a multiple innovation. In the first place, I think
it’s a social innovation, because architects and engineers
are cooperating so closely. Architects are engaged in the design
of the climate system and they are also engaged in the problem
of energy and indoor environment. And that’s of course very important. And also for the people in the building
you can call it a social innovation because the indoor environment is better. Scientists have proven many years ago
that when the indoor environment is better, the productivity of the office staff
is improved as well. And at last it is a technological innovation. We have air conditioning without vents. We can have zero energy buildings
and that’s of course fantastic. We should do that in the future. Some of my favorite statements: the trouble with getting old it that one doesn’t. That means that your body gets old,
but your mind doesn’t get old. Is that a problem? No,
for me it’s not a problem — (Chuckles) but that the body gets old
is sometimes a problem. The most wonderful youth is a youthful mind
when you are no longer young. That’s my favorite saying. It’s from
a famous French philosopher.

30 thoughts on “Air conditioning with wind, sun and water: Ben Bronsema at TEDxDelft”

  1. Dr. Benjamin,

    Many thanks for your clear presentation, stay always young in hart en way of knowledge.

    ir. Gelde MJ Nieuwenhuijzen

  2. He leaves out all the details. This presentation is shit. He's trying to sell his design services, yet there is no proof of concept. He uses 17 minutes to explain what should take 1 minute. He shows drawings that don't tell you much of anything.

  3. Hi Ben… its my pleasure to see your presentation its my dream as well, Its really great work, I'm having an interest of getting every thing at home from natural resources zero in zero out self-sufficient houses moreover a productive houses, organic foods, healthy ,I'm a one person who believe on this dream I know it is huge and I should decompose it into small projects, but I don't know how to get people convinced with the whole project , to give a budget to realize these things is a proposal sufficient? Is it the media? etc…Thanks in advance..

  4. I watched the whole video, but I'm not sure I caught an explanation of how termites keep their hills (or whatever their structures are called) at constant temperature. I would really like to know.

  5. Simple question that he doesn't answer: What happens to all of that "moist water vapour" that comes from the water cascade? It cools the air in the summer and preheats it in the winter, (that's understood). However, where does all of that water vapour go to? Are you using it the "humidify" the building? It could get very uncomfortable to have a relative humidity about 75 percent. No fans to help circulate that air? Water vapour is lighter than air, so it would easily accumulate in the upper floors, (very muggy, even if the temperature is low). Unless you have an arid (dry) climate, you should also be looking at "dehumidification"; but, it's not mentioned in this presentation. Those termite mounds are usually found in arid climates, (not in the Netherlands).

  6. This is an old fix to a constant problem. We used to have these water cooling units on the top of our buildings. Electricity was necessary, when the wind didn't blow, and it was also necessary for the blower. I like the design of a hole in the center of the building to circulate air.

  7. I didn't meet anybody who would complain about air conditioning during hot summer. The ventilation systems have silencers in canals, the air flow velocity can be set up. Heat pumps are quite common. But what he didn't mention is the borderlines for project that determine building height, size, type, surroundings, local law regulations etc – it all has impact on the shape of the building.

  8. Where can we find his research for more detail? He mentioned it was funded by tax money. It is available to public right?

  9. Disappointing talk. He basically described evaporative cooling with a solar chimney for air flow. I was looking forward to something new. Also notice how he hides his one hand when talks about receiving the funding, I don't think he believes he spent the money well.

  10. Wow, termites are natural climate control architects and engineers? What incredible luck! Many of our buildings ALREADY have climate control colonies incorporated within their structures! Hooray!๐Ÿ™†๐Ÿ˜

  11. You are so inspiring. Thank you for sharing your beautiful stories, jokes and most of all your hard work and wisdom!

  12. Am planning to build a single story house in a tropical area how do I apply this natural air conditioning without heating as it is a hot climate

  13. No person who lives in Phoenix Arizona does not complain about air conditioning. We need artificial air conditioning here during the summer. Why? Well even at night it doesn't cool down. It holds the heat. There is no cool air breeze here. For inventers like this guy. You should live a year or two in Arizona and think about natural air conditioning here. But nothing about AC bugs me other than the energy bill here in Phoenix.

  14. Too much lead in. Description rushed, diagrams not labeled. Would have liked to really understand what he was describing. I think the only people that could get anything out of this talk would be those that already ibderstand all the systems he describes.

Leave a Reply

Your email address will not be published. Required fields are marked *