Carbon Sequestration Using the Green Roof
Our team, The Carboneers, is aware of the problem of increasing levels of carbon dioxide in the atmosphere, which leads to many adverse effects. As we are not capable of carrying out large scale expensive projects that require immense resources and calculations, we have decided to select a field that is easy to deal with on an everyday basis. Our work combines the carbon sequestration ability of grass, with the unused wasted space on the roof of cars, along with the multiplying effect of the massive existent number of cars and trucks to give birth to the “green roof,” one previously incorporated on buildings. If all goes as idealized, and this method is adapted, huge amounts of carbon dioxide could be absorbed from the atmosphere yearly, with barely any pain or costs endeared.
Brian Drayton
Co-Director
Interesting, and a fun presentation.
A couple of questions that you may have thought of, but not had room to discuss:
1. Do you mean 58 million tons of C absorbed?
2. How often would you need to harvest the grass to reach this amount?
3. How would mixing in legumes affect the amount of biomass per sq meter?
Green Machine
Hello. Thank you for the comments.
No, we intend 58 tons and not million tons. That is due to the fact that 1000 cars absorb 0.46 tons yearly, not each individual car.
An acceptable amount is once every two to three weeks.
The main goal of mixing in legumes is to eliminate the need for fertilization by fixating Nitrogen in the soil. The biomass is slightly decreased according to some sources, (Grass grows with more density) However the fact that they eliminate fertilization needs and encourage healthy growth makes sowing a limited amount of them worthwhile, despite the fact they are a bit tougher than grass to maintain.
Thank you,
The Carboneers
Susan Leschine
Professor
Hello Karim and Ali, Excellent idea! …greening the roofs of vehicles! Your video is wonderful, very entertaining and informative. I especially like your quantitative assessment of your innovation, that you’ve calculated the potential for carbon uptake.
In your poster, you list some of the “cons” of the Green Roof innovation. I am wondering about two other potential “cons:” water & light. How will you keep your green roof from drying out on long road trips? How will you provide light to vehicles that spend much of their time in the shade of trees or large buildings, or in garages?
Green Machine
Hello! Thank you for the comments.
The beauty of the green roof is in its flexibility, and practicality, as it can be creatively modified very easily by its user. For example, a bottle that periodically or manually releases water can be attached to the roof, or built in. If that is not feasible, simpler alternatives can be adopted, such as stopping occasionally and supplying it with water, or just leaving it at home, where there might be somebody to cater for its needs. It all depends on the length and conditions of the trips.
As for your second question, we mentioned in our poster that the green roof is generally attached to the car, thus it is mobile and can be removed if the car is exposed to complete darkness. It can be stored in a suitable area until it is needed, or until the car is exposed to the required conditions The grass can indeed tolerate light shade however, so shade generally will not impede it. Our figures are also slightly lower than many of our sources to make up for such inconvenience.
Thank you,
The Carboneers
Gillian Puttick
Senior Scientist
Interesting project, and an engaging presentation. You obviously put a lot of thought into thinking about the impact of this method if it was scaled. I was wondering if you’d thought about how to harvest the grass efficiently and conveniently? And how much grass an individual vehicle might need to make it carbon neutral?
Green Machine
Hello! Thank you for the comments.
The grass can be cut using traditional methods, allowing the grass to fall into the soil, which will not harm the soil or growing grass. Alternatively, the tray can be taken off the car and the grass can be collected for other uses.
According to http://www.epa.gov/, the average passenger car releases 4.7 tons of CO2 (over 99% of a car’s carbon emissions), which is 1.25 tons of carbon. As 1000 cars with their green roofs absorb around 0.46 tons yearly, slightly more than 4000 cars will neutralize the yearly carbon production of one car. This is a strong amount relative to the cheapness and practicality of the method, and the fact that car roofs generally wasted spaces.
Thank you,
The Carboneers
Sara Lacy
Senior Scientist
A very attractive idea. I’m wondering about the weight of a 4 square meter tray of soil and grass. Have you estimated the weight? Will this pose problems in getting the tray on and off the roof? Would it reduce gas mileage?
Green Machine
Hello. Thank you for the comments.
The setup is primarily soil, hence this accounts for most of the mass. Assuming the density of the taken soil is 1.2g/cm3, the height of it is 1.5cm, then this will give us a mass of 72kg approximately. The container’s mass is near negligible, and that of the grass depends on may factors, however the overall setup should not exceed 80 kg. It can be carried by a couple of people without too much hassle, although its displacement does not occur too frequently. Alternatively, we have also constructed a different model (Not for this purpose) in which the tray is not one large tray, but is subdivided into many mini trays, approximately 8 trays of different herbs. (We were checking the project on herbs) This can be done with grass though. That would give each tray a mass of around 10kg.In this scenario, the trays can be loaded and unloaded separately without difficulty.(That’s what I meant by the creativity and flexibility of the selected method.)
This is the around the weight of an additional passenger, which reduces the mileage by 1.5% according to http://www.fueleconomy.gov/. Such a change might affect the total efficiency of the method by a limited percentage. (Which is why we used numbers less than those of most our sources, in case of other factors such as extra mass, air resistance…)
Thank you,
The Carboneers
Joni Falk
Co-Director, Center for School Reform
I enjoyed this. Thanks! If you were on shark tank, how would you sell this idea so that it would be adopted by the public at large? Do you think this could catch on? And if not, why not?
Green Machine
Hello! Thank you for the comments!
Sorry, I did not understand what you mean by shark tank, may you please clarify?
In our vision, the idea has potential for development in many ways and sectors. For example, it can be implemented on large trucks in industry. The owners of these vehicles will surely not mind the aesthetic effect, perhaps finding welcome. The grass harvested can also be used economically!
As for the public, this method will surely be welcome by environmentalists as a way not only to aid the environment, but to distinguish themselves in a unique “eco-style.” Another possibility is car companies integrating this roof in the making and cost of the car, which will not affect the prices by a great degree.
But in the end, it all depends on public awareness which is the primary factor in the “masses’” willingness to adopt this method.
Thank you,
The Carboneers