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EarthHack - [sustainable homes] Update 24 Sept 2013:
We have a winner!
Simon Barker of Radfan has taken home the glory with his simple yet clever device designed to circulate hot air around rooms more effectively. 
The remaining prize winners are:
2nd place: Aerogel skylight with integrated LEDs for highly-insulated constant illumination
(Ralph Evins). Honourable mention also for his 2 other very impressive entries in the finalist line-up, "A data centre in every home" and "Evaporative cooling via fibre wicking"
3rd place: Mobile App/Game - Lets make saving energy fun and rewarding! (David Finnegan)
Top voted: Negative Ion emitting LED Bulb (Chris Ratcliff)

You can read more about the winning ideas and the full judges' feedback on Marblar Muses.
Update 30 Aug 2013: That's it then! Idea submissions are now CLOSED, and the judges are deciding on who's going to be the overall winner. Stay tuned! We'll be announcing the winner in just a few weeks at Climate Week NYC.

Today, 16% of all waste generated in society, 31% of all energy consumed, and 10% of all fresh water used is consumed in and around our homes1. This means around a third of carbon emissions come from buildings1, about half of which is from energy or resources consumed in our homes. That’s a total of >5,000 million tonnes of CO2 every year, and a massive chunk of carbon to aim at. It comes from heating, lighting, cooking, air conditioning, appliances, wasted food – almost every use of energy in the home leads directly or indirectly to carbon emissions.

This is why the inaugural EarthHack starts at home. From your home, to homes all around the globe.

People are looking for affordable and simple solutions to help them live a more sustainable life at home. But unfortunately, many sustainable products and solutions are priced at a premium. Moreover, there are many existing technologies that have been developed for other purposes that can be re-imagined as sustainable solutions.

Your mission
Combine, repurpose or modify existing technologies and products to create tomorrow’s practical and scalable low-carbon solutions for the home.

Your concepts will inspire and enable people to live a more sustainable life at home, save money and have a positive impact on the planet. As you and your fellow Marblars build and creatively iterate through great ideas, carbon-saving concepts will emerge that:
  • Reduce energy consumption, manage energy more efficiently and/or generate energy
  • Apply innovative solutions to lighting homes – through efficient use of available natural light, as well as new energy efficient electric lighting
  • Sort and reduce household waste and turn waste into resources to minimize waste to landfill
  • Save, reuse and recycle water and minimise household chemical use at home
The EarthHack [sustainable homes] and your participation will have a transformational impact on the way people and families choose to live their lives at home, enabling a more affordable and sustainable life for the many people. And by “home” we mean an apartment in either New York or New Delhi. A farmhouse in Calgary or Buenos Aires. A shared flat in Bogotá or Shanghai. The EarthHack [sustainable homes] is a global hack. 

As you construct your entry, don’t be afraid to inspire us with diagrams, photos, cost estimates and potential considerations around product design, material, transport and installation and usage at home. In addition, please articulate the potential environmental, societal and economic benefits of your proposed solution(s).

But you don’t need all the answers! That’s what the Marblar community is here for. If you see ideas from others that you find interesting, please join in the discussion to help shape the concept. The EarthHack only succeeds if we all come together. 

Here are some things you might want to think about:

Design isn't just making something look good. Intelligent design – of space, light, interactions – can have a major, positive impact on how much energy or other resources people use in and around a home. Why not re-imagine technology to improve designs of buildings? Or improve design of buildings to take advantage of technology? Whether it's an apartment or a farmhouse; design matters.

Materials science has come a long way since modern mortar was invented more than 200 years ago, so now we make buildings from, erm… bricks and mortar. You can help us do better! There are bucket loads of advanced new structural, transparent, insulation and device materials that could be re-purposed to save carbon in homes.

Homes are systems. Really complicated ones. Full of subsystems. Heating systems interact with cooking systems which interact with ventilation systems – and all currently in uncontrolled ways. Smart systems, sensors and user interfaces could make a major difference and turn these system interactions to a chance to save carbon. How would you re-imagine existing technology to reduce carbon emissions from the systems in a home?
Competition process
On August 1st we'll be shortlisting the top concepts as decided by our judges and assisted by the community feedback.  The Marblar community will then work towards plumping out the finalist concepts. For each finalist entry we shall be thinking more about the feasibility, impact and practical deployment of each solution. All Marblars are welcome to participate in all discussions. If you contribute meaningfully to the idea that wins you'll nab yourself $500. More about the selection process here.

The Climate Group The Climate Group is an independent, not-for-profit organisation working to inspire and catalyse leadership for a ‘CleanRevolution’: a low carbon future that is smarter, better and more prosperous. For all. Founded in 2004, The Climate Group has operations in Australia, China (Beijing and Hong Kong), Europe, India and North America.

IKEA IKEA offers a wide range of well-designed, functional home furnishing products at prices so low that as many people as possible will be able to afford them. This is the idea at the heart of everything IKEA does, from product development and purchases to how we sell our products in IKEA stores globally.

Philips Royal Philips of the Netherlands is a diversified Health and Well-being company, focused on improving people’s lives through timely innovations. As a world leader in healthcare, lifestyle and lighting, Philips integrates technologies and design into people-centric solutions, based on fundamental customer insights and the brand promise of “sense and simplicity”.

Sir Chris Llewellyn-SmithProfessor Sir Chris Llewellyn Smith FRS is the former Director General of CERN, former Chairman of Oxford’s Physics Department and current Director of Energy Research at Oxford University. Previously, he was also Director of UKAEA Culham (2003-2008), with responsibility for the UK's fusion programme and for operation of the Joint European Torus (JET), and Provost and President of University College London (1999-2002).
Professor Sir Richard Friend FRS holds the Cavendish Chair of Physics at the University of Cambridge. Both a scientist and an entrepreneur, he has been at the forefront of development in plastic electronics for use in semiconductor devices including solar cells, light-emitting diodes and field-effect transistors. He co-founded Cambridge Display Technology in 1994, Plastic Logic in 2000 and Eight19 in 2010 and is Programme Director of the Winton Programme for the Physics of Sustainability.
Harry Verhaar is Head of Global Public & Government Affairs for Philips Lighting. In this role he passionately drives the global market transition to sustainable lighting solutions, with emphasis on the 'LED Revolution'. His belief is that this is not 'just' a way to save money and reduce ecological footprints, but most of all is the smartest pathway to equitable development of a prosperous future for all.
Matt Stanley works in IKEA’s Sustainability Innovation team & is focused on identifying, enabling & building new sustainability-related business opportunities for IKEA and its customers that contribute to delivering IKEA’s Sustainability Strategy for 2020 – People & Planet Positive. Matt holds a MSt in Sustainability Leadership from the University of Cambridge and is passionate about working with people and businesses accelerating the transition towards a more sustainable future.
Dr Nick Goddard Low carbon technology finance and strategy expert. Cambridge physicist, Imperial College engineer, 10 years in the City raising funding for early stage companies – two of which ended up in the FTSE100. Now a serial entrepreneur and interim manager, his latest project being the game-changing wind energy capture company Spinetic Energy Ltd.
Dr Robert Trezona Low carbon start-up investment expert. Has spent a decade working and investing in plucky start-ups that are trying to save the world, including Ceres Power and Azuri Technologies. Looking for something to invest in from the EarthHack.
Dr David Raval Low carbon entrepreneurship expert. Former head of the Carbon Trust start-up incubator, which worked with scores of cleantech start-ups. Now CEO of LoftZone, delivering innovative technology to improve insulation of homes. Dave’s showing it can be done!
Will Ray Low Carbon buildings technical expert. Will knows everything and everyone in clean buildings technology. Currently head of The Energy Design Centre at buildings materials company Rockwool and former head of the Low Carbon Building Accelerator at the Carbon Trust.
David Sanders Low carbon expert consultant. David heads up Cleantech Advisory LLP, which, amongst other things, helps start-ups refine their business plans, find customers and raise finance. He is also called in to advise corporates on all things cleantech, including E.ON, ESBI, GSMA, Shell, Tata, and Virgin.
More information
Frequently asked questions

1 United Nations Environment Programme

Challenge Discussion
Jaime Padrón Medina on Sep 12, 2013
Hello you all again,

I would like to post this entry to show two bright ideas. I have no merit at all this time.

As you can see, one of these Ideas (that maybe you already know) can not be simpler nor brighter.

The other one, is just to show you how, investing in energy efficiency is a good business. This is a recently created Spanish company, that want to lead the widespread use of energy monitor devices, in order to make houses and companies save energy and money.
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Jaime Padrón Medina on Sep 09, 2013
It seems that people here are exhausted after this intense competition, but I´m not. I have one new Idea that I would like to share with you.
Why don´t we install "progressive lamps at home"?. What I mean, is that when we buy a Led or Low Consumption Bulb or a Normal Light Bulb, it always works at 100%. But many times this is too much more light that what we need, and normally it can not be regulated. Sometimes, in some houses, people install "potentiometers" that let the users regulate the amount of light of an specific lamp.
Then, why don´t we create LEDS that can be regulated themselves, in order to be able to adapt the amount of light they produce.
Everything that was below 100%, would be saving energy. Just imagine how much energy could be saved if all light bulbs in the world were to be working at 90% of its capacity.
And going a little further, it would be great to have central light sensor in every room, in such a way that all lights were automatically regulated in order to reach the amount of light that the user want, but no more. It will works as LED TV´s do nowadays, that adapts the screen light according to the user preferences taking into account how illuminated the TV room is.


Definitely, A+HOUSE, will have this system installed.

Robert Francois on Sep 09, 2013
Hi Jaime, thats the solution my submission addresses. Yes, imagine the carbon and dollars saved from widespread use.
Jaime Padrón Medina on Sep 09, 2013
Hi Robert,
You are right, I haven´t read your submission. I congratulate you for such idea. Of course this system requires no new technology, and it´s already used in some inteligent buildings. The key factor is to make it commonly used.
The problem of this system, is that it´s expensive, and in current houses, a lot of work is needed to install them, but in new houses, I find it really interesting.

For those cases where it´s considered too complicated or too expensive to do the whole self control installation, I think that the Idea of the LED light bulb that can be regulated individually , it could be helpful, and cost was not to be increased much.

I think in my mother´s house. I know that she would buy a single LED light bulb that can be regulated easily. I my home, I would install the system that you submited.

Nice chat Robert.
Robert Francois on Sep 09, 2013
A little savings here and there can really add up. Thanks Jaime.
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Chris Ratcliff on Sep 08, 2013
Can someone please clarify when the winners will be announced? On the opening page of the competition it states that the winner will be given $3,000 for a flight to the award ceremony at climate week and be allowed to present their idea to the public. On the top of this page the update states that the winner will not be announced until climate week. Which is the proper date?
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Jaime Padrón Medina on Sep 06, 2013
Why don´t we use this elapsed time to discuss about some topics?
I propose one:
- "Isn´t education the key factor in order to reduce CO2 emission?. What I mean, is that we can install the best isolated window ever, that if people keep them open in winter while using heating system inside, it won´t work. In Part L regulation states that instructions should be given to owners in order to "use" the house in the most efficient way possible. Wouldn´t education investment save tons of CO2 emission and millions of $? What do you thing about that?"
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Chris Ratcliff on Sep 01, 2013
What date will the judges announce 1st, 2nd and 3rd place winners?
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Chris Ratcliff on Aug 27, 2013
What is the local UK time on the 28th that the competition ends?
Daniel Perez on Aug 27, 2013
Hi Chris, the competition is closed tonight (Aug 28th) at 11:59pm London time. That is 06:59pm EST, 3:59PM PST.

Hope that helps!
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Ralph Evins on Aug 05, 2013
What is the timetable for judging the finalist ideas? The diagram in "competition process" says 4th Sept (and also 3 weeks from 1 August...), but the "Winner" bar at the top says 47 days (21st Sept). What's the deadline for final improvements to ideas, and when are the winners announced? Thanks.
Daniel Perez on Aug 05, 2013
Ralph - my sincere apologies that there was confusion on the timeline. The winner bar was fixed when you posted your comment here, but I neglected to press "reply" to say that! :)

People have till Aug 28th to refine their submissions, and help plump out other people's submissions. Good luck to all! :)
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Martin Rayman on Jul 21, 2013
Some other ideas:
1)Inflatable mannequin washing mechanism....rather than wash a whole pile of clothes, as needed place clothes on mannequin, which inflates to have close contact with clothes . Zip up outer clear plastic cover to seal. Mannequin has a series of fine holes for water, or steam or drying air. The idea would be to dampen the clothes first with small amount of detergent infused hot water, then blast with short series high pressure bursts, then blast with drying hot air. Give a final inflate to reduce creases. With individual items eg socks, underwear, selective blasts could reduce unnecessary waste.

2)For houses or apartment buildings centralize the lighting unit a small number of highly efficient long lasting lights, but deliver to individual areas via optical fibre. A computer control unit of lens and mirrors determine which bunch of optic fibres to channel light into. Perhaps a return bunch of optic fibres can determine whether there is recent movement in a room or not and selectively reduce light if none.

3)Have mini but tall green house attachments to C02 rich outlets of heating systems for the growth of fast growing low maintenance bamboo, which can be either burnt or sold.
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Martin Rayman on Jul 21, 2013
I know nothing about how this process works but I'll throw a couple ideas, most are bonkers ridiculous or impractical (but perhaps might trigger someone else to make practical), and at least one disgusting (but it might be a cultural thing that is eventually overcome), and perhaps one or two that might be worth being mulled over. (I've just noticed some of these ideas have been mentioned already, sorry for the repeat...consider it a vote of approval!)
OK, here goes...disgusting first
1)suction order to reduce the water consumption, cut out or at least reduce the use of toilet paper. A flexible tube with an adjustable lower pressure (created by foot suction pump for sensitive control) and a very soft silicon rubber head piece is placed in the vicinity of relevant orifice and gently manoeuvred into position. The head piece would have either multiple layers of removable rubber sheeting .... an ouher layer is removed after use by peeling
off, revealing another clean layer below for next user. Or alternatively soft tissue coverings would be placed on top and removed after use and disposed of. In action the user would either activate the pump or even better create under their own power a mild vacuum to help extract solid waste into flexible tube and down into another chamber where it would be blended with liquid waste to more easily flow onto the sewerage system. Or alternatively the solid waste
(without the liquid matter which is relatively safe in comparison to go into the local soil...not sure about that?) could be sucked into say 5cm diameter, 80 cm long transparent biodegradable sealed plastic cylinders, and these cylinders
removed, stacked and temporarily stored, to eventually transported to a processing plant where they are subjected to gamma ray source to kill pathogens, then buried upright in boreholes in the soil to decompose safely over a couple months.
Though this suggestion might be initially unappealing it does cut out many middle men - lots of bulky plumbing, disinfectants, toilet paper, lots of water, and reduce the pressure on the sewerage system.

2)use your roof as a wind generator. Your roof is a large area almost constantly subjected to an airflow on top and little below, but not being particularly aerodynamic doesn't actually produce much lift. However that could change with new designs for roof surfaces that have leading edges and following surfaces used to create sufficient lift to elevate a moveable roof surface say a safe 10cm, before leading edge is shifted removing the lift, and the heavy roof surface drops
whilst generating power via a hydraulic or piezoelectric or other mechanical dynamo. A cycle of lift/drop would be controlled by computer and wind sensors. Alternatively rather than whole roof surfaces moving, banks of computer controlled, piezo-electric tilted aerodynamic tiles would produce the same sort of effect but for smaller subsections of the roof, optimally chosen depending on wind direction, speed etc. Perhaps even aerodynamically unstable tiles, that with minimal piezo-electric adjustment will flicker rapidly between two positions generating energy via electromagnetic coils.

3)Re-design kettles so that they are actually re-enforced thermos flasks, with reflective inner surfaces, double skinned with vacuum between, and energy transfer by means of induction heating into the base of the flask across the vacuum. Additionally (depending on how strong the walls are....they could be metal (or re-enforced silvered glass or even aerogel) with insulating
rubber seals to trap vacuum and stop heat loss), The flask could be sealed like a pressure cooker until boiling occurs reducing latent heat loss whilst getting to 100C. Very smooth inner surfaces to reduce bubble formation and narrowed at top so exposed surface area is small reducing evaporative heat loss.

4)A paint with microscopic flat reflective sheet particles, magnetically orientatable whilst drying to give a surface that reflects radiation back into a room, reducing heat loss.

5)A paint with fine aerogel particles blended in throughout, giving a lower conductivity paint surface

6)Baffles in a ceiling that discourage convection currents down the cold surface of walls or windows. The baffles could be a couple feet away from a cold wall, so that the convection current down avoids the cold surfaces as much as possible. So the convection currents effectively would be trapped within a room smaller than the real room and without cold walls. The baffles would be just wood planks of width 30cm (width ways downward).

7)Its no use making the industrial world better if the problem is shifted to countries less able to manage or resist the short term benefits of environmental degradation, so introduce a 5 star system for grading products in various categories like environmentally friendly, energy usage, sustainability, ethical production, fair trade values based on first a self regulating system where producers are encouraged to grade themselves between 1 and 5 stars (based on a set list of criteria), and then if subsequent revelations show these grading to be untrue, they are
immediately downgraded by a number of stars depending on the severity of the lie. As the system develops and available to on-line shoppers (yes, it would be crude at the start...but most of our regulatory systems started fairly crude), the grading could include the chain of suppliers for a given product. If products were so graded and these grades were available to on-line shoppers, there might be a way for a shopper (say via Amazon) to set up an automatic filtering to show only products that reachs or exceed an online shopper preset choice of minimal star ratings they feel comfortable buying. The threat of even minor economic harm would give companies
an incentive to get more careful about their choice of suppliers and act premptively rather than reactively (eg Primark influencing the clothes manufacturers in Bangladesh). Most shoppers dont know the true cost of products, but if there was a way to simplify into a simple 5-star rating over a couple different categories and restrict viewing according to a shoppers concerns, there would be a way to give power to the shopper to send a strong feedback signal back up the production line.

8)Create high frictional clothes that generate heat near contact to body surface. For example two independent layers of material in close contact moving in opposite directions when say your arms or legs are moved...if movement gave obvious warming effects it would encourage
a cold person to move more and warm themselves. To avoid chaffing the skin the frictional warming would have to achieved by the rubbing of layers of cloth against each, with a static layer against the skin Perhaps even piezo-electric generators in shoes to generator tiny currents feed into heating threads within socks. Aerogel and reflective foil hidden within shoe soles, or incorporated into socks.

9)A functional and educational gravity lamp for children. No amount of lecturing will convince the next generation of the need for energy conservation than having their own bedroom LED reading lamp that they must either wind up or pull a chained weight up so as to generate energy to keep it going. Flicking on (and off) a switch will be much more meaningful after having such a lamp under their own control.

10)Wall lamps like above that are activated by pulling up a weight (eg 2kg bag of sand). Reminds me of a grandfather clock we used to have when a child. Kids could get a kick out of being the bringers of light into the evening

11)A soft coating spray film for body that allows pores to breathe, yet insulates, and additionally absorbs sweat and neutralizes odors. Removing by peeling off the film will effectively clean the top layer of skin, save of body bathing. The film would be soft enough as to not pull against hairs,
maybe just rubs or washes off.

12)Electric clothing, sealed clothes on various surfaces eg

13)Using Bernouilli effect (eg the atomizer spray action use to pull liquids up a tube by the action of air blown across an opening at the top) to create pressure lowering enabling water to be pulled to a higher level by even a moderate breeze funnelled into a narrow passage. Using such
small effects (image a staircase effect of lifting water up incremental steps) over an extended period will fill a large tank with water at an elevated height (err...perhaps...maybe...brain too saturated by rum&coke to work it out).

14)tube piezo-electric generator use in clothes or in flapping windpipes

15)computer control (eg Kinect body locator) local pressured hot air release from in floor (carpet) pores based on sensors locating persons in a room. Hot air rises so warm air would flow around the locality of the person. Perhaps further more acute savings could be to release into soles of special vented shoes and channelled upward inside clothing.
Retrieve hot air via holes in ceiling above the locality could provide some energy savings. The air can be either locally heated electrically or piped into insulated floor cavities ready for use.

16)similar to above but given that floor space is often cluttered whereas ceiling regular stream hot air vortex rings (like smoke rings) downward to the location of person. So ceiling would have numerous possible ring openings and correct ones opened to direct hot air vertically down at person.
Or maybe only a small number of directable vortex ring generators in ceiling instead.

17)this idea almost definitely wont work but might give ideas to build on. Create light traps that consist of light bouncing around inside a polygon but trapped by total internal reflection (meant to be almost 100% efficient reflection if I remember my physics correctly).
Light is trapped during daytime by being first directed along optic fibres to join polygon route at correct angle. Light released later by electrically
induced change of refractive index. (Yeah, right! Just got to sort of nuclear fusion next)

18)Redesign pressure cookers so less bulky, easier to quickly use, easy viewing via re-enforced glass top covers (maybe with embedded wire like some security windows), have a two stage chamber, inner chamber for the main cooking and pressuring, outer or top chamber for quick and easy addition of extra ingredients or taste testing (ie quick compression/decompression...maybe by aid of cooling mist spray to condense steam). This top chamber would go through quick pressuring and decompression as to allow access. Add false bottom to avoid sticking/burning consisting of a slightly elevated plate with holes ie so liquid goes down but solids stay up, add stirrer that doesnt break
pressure seal eg rubber or one of those putty rubber or thixotropic liquids that stiffens under pressure. Perhaps a thixotropic seal for the pressure cooker.
Such a pressure cooker would be great in 3rd world countries where beans, pulses, and root vegetables that need long boiling times are often staples.

19)Foam paint...paint which on application releases CO2 and so produces a slightly foamy surface and so becomes less heat conductive

20)Hairy walls/carpet walls to trap pockets of air and reduce heat lost, and then in hot summer use capillary flow to bring water up to cool walls/room.

21)water droplet mist vortices aimed at recipients for localized cooling

22)damp sponge enclosed in cuffs collars socks (near passing arteries) for summer cooling clothing range. Recharge sponge with bottled water via decorative holes

23)misting sprays at windows to encourage mist laden air blown into room in order to cool room. Bernoulli effect driven mists.

24)very fine mist sprays in ceiling to lower room temp

25)mobile app for constant monitoring of electricity metering....helps awareness of useage and conservation, with noticeable feedback (nice audible sound) when items are turned off.

26)localized warming chairs activated by sitting on them....often if part of body is warm, the effects of cold are easier to take

27)inductively heated clothes, slippers from inductive coils in furniture or flooring

28)warmed sponge showers....a shower with multiple sponges that slowly exude warm water, and absorb back, filter and reuse the warmed water whilst rotating, and another lot of absorbing towelling surfaces that dry, reducing water used minimizing water usage and giving a nice warm
massage in the process

Got to go...need a top up of my drink now!
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Dave Raval on Jul 16, 2013
Hi there, I’ve seen that several of the ideas milling around in the brainstorm are around footfall energy harvesting. This seems an intuitively attractive idea, so I wanted to do the maths of how big an impact this type of technology would have.

Firstly, we need to know how much energy can be harvested from a single footstep. The Dutch company Sustainable Dance Club claims to have “the world’s most efficient converter of human footfall into electrical energy”, and they quote power generated of 5W for a step. They use “an electro-mechanical system, since the potential power output was calculated to be much higher when compared to other systems such as piezo and hydraulic systems”. I have in the past looked at some other piezo systems and they were quoting as little as 1 joule of energy per step (a joule is a watt of power sustained for a second). Anyway, these numbers give us an order of magnitude.

Next, how are we going to capture all these feet walking around? Obvious locations to place harvesters are urban centres, sports stadia, mass transit systems, etc – anywhere where a lot of people walk, repeatedly.

So let’s do the maths on one hypothetical example. Let’s say that a city with a mass transit system (e.g. the Hong Kong Metro or the New York Subway) installs footfall energy collectors at the entrance and exit of every station in the city. Let’s say they get 10million people per day going to work, and 10million per day going home. And say that each person steps once on a collector, each way. That makes 20 million steps per day, Monday to Friday. Let’s assume Saturday is half as busy and Sunday is only operating at 25% of the week day numbers. That’s 115 million footsteps a week – a lot!

Let’s turn that into energy and let’s be generous and assume that 5W is the power generated for the whole duration of each step. But how long does a step last for? I walked up and down, timing myself, and I reckon I can easily do 2 steps per second. So let’s say a step lasts for half a second. That might be a bit generous; I’m not sure the kinetic energy of my foot pressing on the device lasts a full 0.5 second, but let’s go with that. Each step therefore generates 5W x 0.5 seconds = 2.5 J of energy. The unit of energy that we usually use for domestic consumption of electricity is the kilowatt hour (kWh): 1 kWh is 3,600,000 J. Therefore each step generates 0.000000694 kWh Going back to our 115 million footsteps per week in this mass transit harvesting system, we can do the maths: 115m steps x 0.000000694 kWh = 80kWh per week.

In the UK, 1kWh of electricity is about equivalent to 0.5kgCO2. If that’s the same around the world, that means that each mass transit system saves 40kg of CO2 per week, or about 2,000kg per year.

Now this Marblar competition isn’t about mass transit systems, but instead about our homes. Footfall in homes is likely to be less per collector. So, in my personal opinion, it’s going to be a tough challenge to scale up enough footfall collectors to make a big different to carbon reduction targets.
John De Rivaz on Jul 16, 2013
How about boots or shoes where you put a rechargeable battery in the heal and it is charged up (eg from piezo electric soles)? A companion device, such as a small tablet computer or telephone, would use the same battery. This benefits the individual, who would be motivated to pay for the boots, so no one else needs to put up money.
Dave Raval on Jul 16, 2013
Hello John, yes, such micro energy harvesting could indeed be useful for low power devices :)
The form factor of the shoes would need to match the battery shape, but that's always possible.
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Robert Trezona on Jul 15, 2013
As we move into the final few weeks of the brainstorming phase, I thought it would be useful to list a few areas that could offer exciting carbon-saving opportunities in the home, but have NOT YET been reflected in the entries to date. So --- if you're thinking of submitting something in one of these areas but haven't yet done so, then please go ahead. They could be very interesting.

Under-represented areas:

1. Clever models for reducing energy used for space heating or space cooling (i.e. the heating and cooling of air, rather than water, which has had plenty of entries)
- Passive elements (moving hot and cool air around using density differences)
- Best use of solar gain
- Intelligent shading to reduce AC loads
In warmer countries AC is a massive use of energy in the home and a major source of carbon emissions, while in colder countries like the UK space heating is the single largest energy use by most (older) homes.

2. Cleaning, clothing in particular (uses water and heat)
- Reduce demand for it through behaviour change or clever design
- Reduce quantity of water and/or heat required

3. Low energy cooling
- Use of water evaporation
- Alternatives to standard mechanical cooling like magnetic cooling

4. Emissions reduction by intelligent design
- tools to maximise use of light, heat in a home environment

5. Local energy storage: one for the engineers
- Compressed air
- Gravitational
- Heat
- Electrochemcial (e.g., Flow cells, cost effective battery storage)

These are all ideas where there may be carbon opportunities; they are not preferred to the current set of ideas, just represent areas where new competitors may be able to make their mark.

I hope that's useful and good luck if you decide to come in with a new entry
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Walter Feuchs on Jul 11, 2013
The idea of a "World House" was demonstrated at the UN in NYC. The Energy Star, hurricane and seismic rated abode was assembled in 30 minutes. Images available. A fiber composite version of the building envelop eliminates traditional framing, sheathing, siding, drywall, roof trusses and roofing. The panel size is 8 ft x 40 ft. Cam action fasteners result in the building envelope being 100% recyclable. The panels are insect, water and fire resistant. They are applicable to residential, commercial properties, as well as retrofitting existing structures. The panels are also bouyant (think solar house boats). Photos available.

PV's can be integraded in the production stage.

Production facilities are in place in the USA.

We are an entry in the Innovations Pavilion of the Solar Decathlon 2013 in Irvine, CA (Oct 3-13). We will assemble the major components of a zero energy house in one hour. In the USA, a house that energizes itself and a form of transportation saves a household $908,450.33 US in the course of a 30 year mortgage, when compounded.

Also shown is a LEED rated composite that has thermal properties of NASA Space Shuttle tiles. The composite permanently fuses to a substrate, with PV's embedded at the "setting' time of the composite....thus "Solarizing the World on the Cheap". America's toughest building code body declared this development as "Revolutionizing construction", The Hurricane Testing Laboratory (HTL) had no criteria for testing!

The composite will also be offer as an interior radiant heat source, allowing zonal temperature controls.

An exhibit is planned in conjunction with Abu Dhabi's World Future Energy Summit 2014, in January.

The US Government has not supported the foregoing game changers.

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Dave Raval on Jul 09, 2013
In reading the many entries to this competition so far, I've seen that several of them have been around the theme of saving water. Water is a scarce resource in many parts of the world today, and saving it is therefore a key priority for any environmentalist. However this does not necessarily mean that it should automatically be put into the same category as energy saving or climate change, the two issues are distinct and it’s worth doing the maths to sort out the difference. So I thought I'd write this note on the subject.

Water usage can generate carbon in several ways:
1. Civil engineering works to access sources of water, store and transport it (e.g. building wells, reservoirs, aquifers and the like)
2. The creation of water utility companies with offices, staff, maintenance works etc, i.e. the ‘indirect’ energy costs of a whole industry
3. Energy costs in transporting (pumping) water from the source to your property, and then back from the property to the treatment plant. This may need to include a factor for leaked water, if leaks are common
4. Energy costs to treat waste water to clean it for future use or discharge (e.g. into oceans)
5. Desalination energy costs (if you are originally extracting your water not from fresh sources but from the sea)
6. Energy costs to heat water if you need to do so in use (e.g. boiling a kettle).
7. Energy costs to pump water within your property (assuming the pressure of the supply is insufficient).

For the purposes of Marblar, I’m going to examine only the marginal energy savings arising from new innovations. Hence I’m going to ignore (1) and (2) on the basis that these infrastructures already exist and a device that saves 5% water (say) is not going to have a marginal impact on these. Clearly, if we get a transformational innovation, that assumption may need to change!

I’m also going to ignore (6). This isn’t because it is unimportant – quite the contrary - according to the UK Energy Savings Trust (quoted here: , 89% of the energy used in water in the home goes into heating it. But that is specific to the application and so the savings calculation is dependent on the energy saving in the application. So please do calculate these for your innovations but it’s not the subject of this note.

Finally, the last thing I’ll ignore is (7). Most people in the UK at least don’t need this, as the water supply is pressurised sufficiently. The most significant pumping energy cost in buildings is when water-based heating solutions are used, e.g. to pump hot water to a radiator, but that isn’t really the subject of this note.

For (3) and (4), the data for the UK was produced by in the link previously mentioned by Will Ray ( This shows the carbon cost of pumping water to be around 600kWh per million litres of water and the carbon cost of treating waste water to be (very approximately) the same (in 2007). I then checked this against the UK Government’s own data for 2013 and this is a bit different, showing 344 kgCO2/mL for water supply and 709 kgCO2/mL for water treatment (I downloaded the frequently used conversion factors table from www.ukconversionfactorscarb...) . But either way, they add up to around the same, i.e. about 1,000kg (1 metric tonne) of CO2 per million litres of water.
So, to get to our target 1 million tonnes of CO2 per year target, that means saving one million million (1x10(to the power 12) litres of water per year. [By the way, I would write that number properly but this text editor doesn't seem to permit superscript]. In the UK we use about 150 litres of water per day in our homes; over the total population of the UK of around 65million people, that equates to 3.5x10(to the power 12) litres of water per year. This gives you an idea of the size of the task. We need to save a *whole* lot of water in order for the energy savings to be significant for climate change. Indeed, I’d suggest that, on a wider scenario, water usage in industry is much more significant (although out of the scope of this Marblar competition). For example, a cup of coffee takes 140 litres of water to make, a kg of beef 15,000 litres of water (both data from WWF) and a pair of San Francisco Levi jeans around 10,000 litres of water (Google it!)

Finally, we mustn’t forget (5). Desalination only applies to some countries, where insufficient fresh water is available. The most efficient plants seem to require as little as 3kWh/m3 (or 3000kWh/mL) for the desalination process ( and To convert this to CO2 you’d need to know the local conversion factor. In Australia, for example, 1.0kWh of electricity uses up about 1kgCO2 (nice and easy to convert, which is why I chose Australia! lol) – data from So that adds another 3tCO2/mL of water. Assuming transmission and sewage energy costs are the same as the UK, that means that Australian desalinated water is four times as energy intense over its whole cycle as UK fresh water.

Dave Raval
July 2013
Shane Pisko on Jul 09, 2013
in response to our use of water and recycling it, i had a thought on how the use and accessibility of hot water is seriously excessive. Why do we have hot water available at all times, when luke warm or only mildly hot water would use less energy. I think taking the option of hot water being available in every facet in every home would be a big energy help. We really only need hot water for a few things, and for those things it could be said that we do not need hot water waiting in reserve, but instead heat up only what we need at that moment. So rather than having water heaters, just heat up what you would need for the particular task, be it a shower or dishwasher.
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James Stork on Jun 25, 2013
Through my net research, I have discovered Geofoam blocks. They are non cfc styrofoam blocks that are currently used as lightweight fill material for roads and approaches where earth material is too heavy or not practical. A road surface is placed on top of the geofoam blocks which can be manufactured in different sizes and densities. I thought that if a road can be built on these blocks, why not a house. Even with a deflection rating of 5 psi (I believe it can be made for a deflection rating of 10 psi), that works out to 720lb per square foot. The blocks come in four by eight by two foot dimensions so for a wall that is two feet thick, the compression rating would be 1440 pounds per lineal foot of wall. That would easily support a roof load. horizontal strength could be bolstered by gluing the blocks together and precompressing the walls through to the footing. This would also avoid any settling issues. The r-value of a two foot thick wall would be at least 90 at a low estimated r-value of 3.75 per inch. The blocks could be as thin as twelve or sixteen inches and keyed like lego blocks for easy construction. They could be finished with almost any coating. I am not an engineer and don't have the money to consult one. I would love to build a sample structure from geofoam blocks but government regulatory processes make it prohibitive for me. Check out "geofoam blocks" or to start. Roads and embankments are ony one use. That stuff just makes my mind run wild.

The Japanese are already making styrofoam dome homes that are seven inches thick and typhoon and earthquake resistant. Check out as well.
Steve Cline on Jun 25, 2013
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Steve Ulrich on Jun 21, 2013
In California especially, a project that would help fight pollution would be to paint your exterior walls with Air Cleaning Paint, like KNOxOUT, distributed by EcoDistribution, Inc.
KNOxOUT Paint is the only paint in the world that actually cleans the air.
Through the proprietary application of a special formulation of TiO2 (a common pigment used in most paint) a chemical reaction is set up in KNOxOUT Paint that removes pollutants including NOx from the air. The great news is that KNOxOUT paint is able to do this by creating free radicals from energy supplied by the sun, and atoms in the air. It does not create any volatile by-products, and it does not break down the paint.
For more information please visit
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Robert Trezona on Jun 18, 2013
The other judges and I are enjoying all the energy and ideas that are coming on the site. Here are a couple of points which may be useful
- Join the Google+ Hangout this afteroon (18 June) here to hear from the people behind Earthhack and learn more about the low carbon space
- If you would like to enter the competition and submit an idea, please do so via the "Brainstorm" or "Add Idea" buttons, rather than on this board, which is for general discussion (though the nice folks at Marblar will port your contribution over...)
- To follow up from Matt from IKEA's post, a lot of the ideas would be improved by some additional description of how you would take your solution to market. IKEA and Philips are really interested in this competition and are looking for new low carbon products that could be marketed to millions of people
- You can continue to add to your idea in the discussion below. This is part of the evaluation process, and any contribution you make will be considered

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Kim-Wui Chee on Jun 13, 2013
Just like 3M has its IR/UV film for the windows to reduce the heat in the room, it is possible also to do something on the wall. Most residential flats or condominium are build using bricks and cement. Such wall gets heated up when it get direct sunlight, and this will not only warm up the room, but more energy are needed from the air-condition to somewhat cool down the wall.
The idea is to have tiles that are made up of soft-gel. Like one of those “cool” patches you put on your forehead when you're having a fever. The soft-gel tiles that are pasted on the wall act as a heat dissipate or heat sink. Decorative design can be put on the surface of the sol-gel tile so to get acceptance from home owner who will be using this product.
Guillem Kowalski on Jun 13, 2013
A possible way of doing what you say might be using Phase Change Materials (PCM). When reaching certain temperature PCM melt and are able to store energy, once the temperature decreases below the melting point they go back to its solid state on an infinite loop. Chemical companies like Basf are really into it right now.
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Vas Anand on Jun 12, 2013
Water... How about a simple system to recycle the humidity generated in a home and bring it back as brown or even (some day) clean water? This could be easily added on to an existing HVAC system, some of which already incorporate dehumidifiers. The only thing to do would be to add a cleaning/ collection/ distribution chamber system...
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Mike Halliday on Jun 11, 2013
Will we ever see the day when each house has its own sewerage works in their gardens? Small scale waste recycling plants buried underground like oil or septic tanks that use natural bacterial to breakdown waste and process solids and liquids back through the house? We may get 2 uses out of our waste water before it is too contaminated to re-use and solids could be ejected as hard pellets for composting on the garden?

I don't know how large scale sewage works operate to compare? May be I need to look on wikipedia!
James Stork on Jun 11, 2013
Properly done, we could also produce methane for local consumption from our biowaste. They have done this for decades in various regions of the world. I have also thought in depth about having a berm style septic system sealed from the earth by a membrane to prevent groundwater contamination. If the system has enough area or water hungry plants, the residual water will not be an issue. Most of us don't use our front lawns for anything but mowing anyways. Excess effluent could be passed on to the municipal system if required. The potential configurations are almost limitless. Once again, many minds are stifled by regulation.
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Mike Halliday on Jun 11, 2013
Why has no one created house bricks that have built in solar panels wired to the mains? - Every house would then be able to generate its own power and possibly feed back into the grid? Initially the cost may be prohibitive, but as mass production kicks in, the cost is driven down.
Vinayak Dave on Jun 11, 2013
Your idea does sound interesting.. But the problem with bricks is that they take a long time to manufacture. Instead concrete bricks are easy to manufacture and do not require additional heating (the kiln). And they cost almost the same! We have gotta consider the carbon footprint as well.. Solar panels are not necessarily a great solution as one has to rely on the sunshine, which is not constant..
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Mike Halliday on Jun 11, 2013
ALL TV Manufacturers need to be forced to include a power switch on all new TV's. Standby mode, even at '<4W x how ever many tv's are on standby' is a huge over generation of power. Our local council gave away free remote smart switches (to the old folks) that work with the existing TV remote to completely shut off the TV at the socket. Over the life time of the TV, this will save significant amounts of power from being wasted.

Maybe new house builders could include a smart socket specifically for the TV (1 in every room) so that from day one the home owner is saving power?

Sergio Lazzarotto on Jun 11, 2013
Today modern LCD TV have a standby power consumption in between 30-50 mW that because on new standards implemented since Jan 2012.. Your socket remotely controlled will need to be powered, so the question is infine what is the real power savings considering that you'll need to power a circuit that will have to switch on the power line. As far as I know only one patent exist that allow to do that remotely through wireless.
John De Rivaz on Jun 11, 2013
Another alternative would be a small solar cell/ rechargeable battery system that provides the standby current. The cell could either use room light or be put in the window with a connecting wire.
Sergio Lazzarotto on Jun 11, 2013
Technically from an energy harvested view point it would certainly work if you put it on the low voltage side of the transformer, however from a usage view point I'm not sure as usually screens are place in shadowed areas to prevent sunlight reflexion on the screen reducing the image contrast. Consequently the size of the cells would have to be of few sqcm which works against today TVs industrial design. Putting such system on the primary of the transformer will face a substantial issue of of voltage and current supply.
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Peter Brewster on Jun 08, 2013
Flooding is causing massive amount of financial hardship my idea is to build a lightweight house and garage on an expanded polystyrene foam around a central pipe that has all the utilities running up it, when the waters rise the house floats up the pipe and no damage, you carry on sleeping and in the morning if the waters haven't receded get the boat out the garage and off you go
Peter Brewster on Jun 08, 2013
And then we can build on flood plains
Aaron Jones on Jun 08, 2013
I can't imagine this taking off, for a number of reasons. 1) Who want an ugly pole sticking out their house. 2) The drag force as a result of water passing by the house would probably bend or snap the pole. 3) If it is a single pole there is the possibility for the house to spin, tearing the connections. 4) A maximum height of the pole would need to be pre decided, so if the flood exceeded this the residents would drown. 5) There would be a large maintenance bill etc
Peter Brewster on Jun 08, 2013
Al you mention can be sorted at design stage 1: people who have no home would not give a fig about a pole, that's just your perceptional reality upsetting your aetsthetic and has no importance, 2: talking about proper design not a silly little pole, 3: pole could be shaped to stop spin or maybe Wow 2 poles, (this is only the initial stage and everything would need to be looked at) 4: a maximum height could be increased or just get in your boat if it get that deep, I mean a 40ft flood we could manage after that it becomes kind of irrelevant, and 5: no more of a maintenance bill than a normal house also less building cost, as you use wood or composits so less weight less cost more strength, please learn to think before just commenting apologies for being so flippant....
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John Prewer on Jun 07, 2013
In my entry (Homes which don’t contaminate the land they stand on, and store heat and coolth in the ground). I forgot to mention that the type of home I am describing (as shown in the book I use as a reference) is two storeys high with a mezzanine (it extends over the external access corridor) which doubles as an study/office /bedroom overlooking a two storey high living room. Which means the area of the home is significantly larger than the home's 3 car parking bay footprint suggests. Is it too late to add that information?
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Chris Mansell on Jun 05, 2013
More people are living in cities than ever before. In 1950, only 30% of the world's population lived in urban regions; today, more than 50% of us do so; by 2050, this figure is expected to reach almost 70% [1]. I was thinking that perhaps we Marblars could focus our thoughts on urban dwellings so as to get the biggest market for our repurposed, modified, low-carbon, technological solutions.

Interestingly, city-dwellers have lower carbon footprints than people who live in rural areas [2].

[2] ;
Pete Wadsworth on Jun 05, 2013
There was a short film / news Item about a Flat in Hong Kong where the Walls all moved around, So each room was small and closed up when not in use. -

Using this idea across a number of Flats, we could reduce the amount of space required by Half and thus get twice as many people in the same space
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Sergio Lazzarotto on Jun 04, 2013
Use of electronically controlled "sunlight tunnels" for mirror orientation control toward the sun, the same that the Egyptians used in their graves or pyramids to light up offices areas during sunny days.
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Sergio Lazzarotto on Jun 04, 2013
Harvest the electronic equipment heat expelled from a device with a thermocoupling component to charge a battery that will power a low power switch bridge between the wall plug and the device power socket, to reduce "gost energy" due to standby without having to modify the equipment. The "smart bridge" can embed an IR Power on / Power off command for remote power On/Off. Standby power can be reduced to as low as few mW.
James Stork on Jun 04, 2013
Also know as peltier junctions. The Russian soldiers supposedly use such devices to power radios during World War Two using a candle or fire source. These junctions as you mentioned can be used to make electricity, but can also be used to cool or heat objects. Just like the small electric coolers. Years ago, I read about a company that wanted to produce electricity from the waste heat of furnaces and other heat producing appliances such as a hot water tank. I don't know how far they got, but I suppose there is potential, especially with modern technology. It's fun to play with. Just get two wires of different conductivities, twist two ends together, place in a candle flame, and measure the voltage with a voltmeter. Fun stuff.
Sergio Lazzarotto on Jun 04, 2013
Currently application using such components have demonstrated to produce with a 5-10 deg. K of temp. gradient, enough power to power electronics including small motors. All those technology pillars exist its only a matter of putting things together in the right way. One should just know how to do it.
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Sergio Lazzarotto on Jun 04, 2013
Pressure of water in waterpipes all around the home is something that is out of people control. However in each home water pipe there is enough pressure so that people can still collect water and activate a small rotative generator that can produce energy to light up some areas. You take a shower, the LEDs light in the shower area are powered by the extra pressure in the water pipe driving a small electromagnetic generator.
Olivier Rossignol on Jun 04, 2013
You are better off using the water falling from your gutters. I have a well and it take a pump to bring the water up and a pressure tank to pressurized the water line.
Sergio Lazzarotto on Jun 04, 2013
Hi Olivier, I have a well as well and use an electric pump either, however that is in my vacation house in the middle of nowhere. In my principal house in a 500k people city, the water is delivered by the city admin .... And here is where this could be used. It is the same for wind power, it can only be used in areas where there is often wind.
Olivier Rossignol on Jun 04, 2013
It take energy to move water. It could be through pump houses all around your city or pump up elevated tank and redistributed with gravity.
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Rachael Ologunde on Jun 03, 2013
Whats the maximum number of words required and when is the deadline?
Mehmet Fidanboylu on Jun 03, 2013
Hi Rachel,

There is no maximum word limit, however I would encourage you to keep things concise. You have 65 days to add your idea into the brainstorm before the best ideas are selected by the judges to be taken forward to the Refinement phase of the competition.

Good luck!
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Olivier Rossignol on Jun 03, 2013
Investing in carbon negative material like hemp is the answer to our fossil energy addiction. You can make everything from the plant. How about a table made from hemp?
Tim Tim on Jun 03, 2013
I developed novel furniture using new materials some years ago, so I could see Hemp being very easy to create new furniture materials that are both rigid and flexible. Possibly with both factors used in one integral piece.

In London we had a furniture development business with Herman Miller, Knoll, and other European makers as clients. I would be surprised if Hemp weren't on the new materials list by now. And if not it certainly should be.
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Matt Stanley on Jun 03, 2013
Off to a quick start! Definitely some good ideas coming through but it would great to think hard about how some of these ideas can be commercialized and scaled to enable millions of people around the world to live a more sustainable life at home! At IKEA, we want to make a big impact on both people and the planet!
Olivier Rossignol on Jun 03, 2013
IKEA needs to start farming hemp.
James Pulver on Jun 03, 2013
Ikea needs to have city stores for people without cars
Tim Tim on Jun 03, 2013
Or they need really cool car parks that are also social spaces:
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