rough rough incomplete first draft

With the substantial amount of research conducted regarding climate change, it is widely believed that the burning of fossil fuels, deforestation, and other human activities are adding a significant amount of greenhouse gases to the atmosphere. These greenhouse gases include carbon dioxide, methane, chlorofluorocarbons, and nitrous oxide. It is furthermore believed that this is enhancing the greenhouse effect, leading to a gradual warming of the Earth’s surface. It is essential that these gases emitted from human activity be constrained in order to avoid exacerbating the warming of the Earth.
The effects of climate change are multifarious. It is a direct threat to human health. It could lead to rising sea levels, agricultural, forestry, and ecosystem disruption, and an increase in the spread of tropical diseases. It will bring intense heat waves and violent storms will occur with more frequency and with more destructiveness. These effects are not expected to be uniform. The potential of such devastating impacts on a global scale make climate change one of the most consequential environmental challenges we must deal with.
As the price for petroleum continues to rise and the demand for it increases exponentially, biofuels are steadily gaining more ground as a possible alternative to our current unsustainable means of transportation. Hydrogen, ethanol, and biodiesel are at the center of research seeking to find an alternative source of fuel to power our economy. These fuels are appealing because of their renewability and in most cases, their cleaner emissions. Biodiesel, made from vegetable oils and animal fats, is at the moment, considered by many to be the best alternative to oil.
Among the most cost and space effective options for a renewable biofuel source are microalgae. As a result of their simple molecular structure, microalgae are the most photosynthetically efficient organisms on the planet and it is because of this that they are also the fastest growing organisms. Every few days, microalgae complete an entire growth cycle. Certain algal strains can consist of hydrocarbons that make up 75% of their dry mass and therefore provide significantly higher yields of oil than terrestrial oilseeds (Banerjee 246). These hydrocarbons can be converted into petrol, diesel, and turbine fuel. Another advantage algae have over other terrestrial biomass sources is that they do not have to compete for land with agriculture. Because of the immense variety of algae and the diversity therein, it can be grown in a wide geographical spectrum.
There are three crucial ingredients for algal growth: sunlight, carbon-di-oxide, and water. If these three criteria are met, algae can be cultivated from lakes, streams, and ponds. However, since these bodies of water are exposed to the elements, they are extremely susceptible to various forms of contamination such as other species of algae and harmful bacteria. Additionally, the strains of algae with the highest oil contents reproduce at a rate much slower than that of the less desirable ones. The faster reproductive rates of those species will eventually starve the oil producing strains of its necessary nutrients. As a result of these problems, very few algal species have been successfully cultivated outdoors (http://www.oilgae.com/algae/oil/biod/cult/cult.html)
Despite this, open-air systems remain the primary means for microalgal biomass production on a mass commercial scale. This is largely due to the cost-effectiveness of such systems. In these commercial productions, the cultivators typically use a shallow raceway pond. In this design, a paddlewheel continually circulates the microalgae around a raceway track, suspending the species at the surface of the water so that it may receive optimal irradiance levels. These shallow raceway ponds are designed so that a source of carbon-di-oxide can be poured in and efficiently captured by the microalgae.
There are numerous sources for waste carbon-di-oxide; essentially, anything that combusts fuel for energy could be used. Algalculture farms could be potentially used as a means of carbon sequestration. Early researchers of the field envisioned farms that could be designed to capture the carbon-di-oxide emitted from industrial gaseous waste streams and utilize it to enhance growth (Hase 157). The gas stacks of coal and other fossil fuel powered plants produce emissions comprised of 13% carbon-di-oxide. Pairing an algalculture farm with power plants would be an excellent way to divert emissions that would otherwise be harmful and convert them into a usable liquid fuel.
However, the majority of algalculture farms are not yet at this point and many experience difficulties in providing the microalgae with sufficient levels of carbon-di-oxide. Because of the short absorbing path of carbon-di-oxide, these farms use organic substances such as acetic acid and carbonate as the primary source (Hase 157). These substitutes limit the overall productive efficiency, lowering total yields and slowing the algae’s growth period. This problem is further exacerbated by the farmers’ inability to control water temperature and irradiance levels. Open-air farms, therefore, have a limited growing season.
Several solutions have been devised to increase the efficiency of these open-air raceway culture systems. The alternative that I chose for my system is a scaled down raceway system that is enclosed by a greenhouse. This will drastically reduce the risk of contaminating sources invading the microalgae. It will allow me to have greater control over the culture medium than one would have in an open pond.
Before beginning construction, I designed several potential tanks. After deliberating as to which design would be most efficient as well as cost-effective, I decided on a tank with the dimensions of 8 ft. x 2 ft. x 2 ft. In retrospect, the height of this tank is perhaps a bit too high and shorter height of 1-11/2 ft. would have been sufficient. I believe that the larger height blocks out slightly more sunlight than is desired but that will be determined.
The tank is mainly constructed of oriented strand board which was selected over plywood because of the much lower levels of formaldehyde emissions, which I saw as a potential source of contamination. The OSB is supported by 2x4’s on the base, the top, and on all eight corners. As an additional safety measure to ensure that the tank would not blow out due to the pressure of the water, I braced the tank with six iron bridge connectors, three on the top and three on the bottom.
Prior to this, however, I first lined the tank with painter’s plastic. This was secured by nailing 1x4’s on top of the plastic on the top rim of the tank. The excess plastic was then removed with a razor.
The next step was to create a baffle system inside of the tank that would aide in the circulation of the microalgae. This was done by securing three small sheets of metal sheathing to 2 1x4’s attached to the north inner wall. Each sheet was scrubbed with hypochlorite to reduce the risk of potential contamination. See diagram 1.0 for details.
Solar heat gain……………..
Details of the greenhouse…………..
Pump system…….
Filling water and purifying……
Algae selection and uses…..
Experimental data……
Conclusion………….