The environment and mankind’s way of life are both in serious jeopardy. Oil, man’s main energy source, is fast depleting. This leaves earth’s environment severely disrupted, and lacking a resource that we have come to rely heavily on. Oil contributes to many of the things that are part of our day to day lives, such as fuel, plastics, asphalt, tires, petrol chemicals, pharmaceuticals, and almost all major manufacturing processes.
My passion for Renewable Energy manifests itself through the devotion of me expanding my knowledge in this particular field of research. I have pursued this knowledge independently since I was sixteen years old by going to conferences across the United States, and researching different ideas on the internet. Now twenty years of age, I am attending The University of New South Wales in Sydney, Australia, which offers the only full program of study in Renewable Energy Engineering in the world. Though this program is expensive, I believe that I can find a way to make it work.
Upon finishing my degree in Renewable Energy Engineering at the UNSW, my goal is to make my family’s 1500 acre dairy and cash crop farm a zero net producer of Carbon dioxide (CO2)
whilst, at the same time, increasing the farm’s revenue. In doing this I hope to turn our farm into a model for people to learn about sustainability, and set a trend in industry by showing that increased revenues are possible without harming the environment. I can achieve all this by integrating many already well established renewable processes into a self-integrated cycle.
As the first step of this sequence we will produce biodiesel. Biodiesel is an environmentally friendly fuel that is not made from petroleum, but from fresh oil that is pressed from the seeds of a farmer’s crop. Soybeans are the traditional crop used for the production of biodiesel in the United States, but are impractical for producing biodiesel on a scale that would help offset the demand for petroleum fuel. This impracticality is due to soybeans only being able to produce 30 gallons of oil an acre, and would require massive tracts of farm land.
Instead, we can look towards algae as being the crop of choice. Algae can produce 3000 gallons of oil per acre growing in photobiotic reactors. These reactors are large glass tubes, two feet in diameter, which are extremely conducive for algae growth when supplied with nutrients and CO2. Also, since the algae is closed off from the environment, it has essentially no need for pesticides and herbicides. Adding to the benefit of algae is that it can be grown in areas that are unsuitable for row crop production. These areas that can be utilized range from land that is too rocky, wet, or steep to grow row crops on, to the roofs and sidings of buildings. Algae is also advantageous as a biodiesel crop, because it can be grown throughout the length of the year. This means that the farmer will not have the expenses of buying seeds, and cultivating large land areas for the algae crop, increasing the farm’s profit.
After growing the algae, the plant is sent through presses that extract the oil. This leaves us with algae oil and a solid algae biomass. The algae oil is sent to the farm’s onsite biodiesel refining facility, where the biodiesel is produced; leaving the farmer with environmentally friendly fuel to run his equipment, and fuel that can be shipped out and sold to the consumer at the farm’s own eco-friendly gas station/grocery store that promotes and educates sustainability to the consumer. This leaves the farm with a two-fold profit from the sale biodiesel, and the lack of expenses in having to buy fuel to run the machinery. As both the consumer and the farmer use this fuel, they are adding essentially zero CO2 emissions to the environment. This is due to the CO2 in the fuel being previously extracted out of the environment by the algae plant as it grew, and the consumer/farmer is now only re-releasing the CO2 back into the atmosphere.
The second product after the pressing stage is the solid algae biomass. This biomass, rich in nutrients and antioxidants, is grown without the use of pesticides and herbicides, and can be added to the cows feed ration as a protein supplement in amounts determined by the dairy’s nutritionist. The farm then has eliminated the cost of buying protein supplement.
The cows, on their diet of algae supplemented feed, produce two phenomenal products: milk and manure. The added health benefits from the algae attributes to an increased yield of milk. The milk is then piped to the farm’s on site dairy processing facility, is processed, and shipped to the farm’s convenience store.
The other, manure, has historically been seen as a waste product, but can now be seen as a resource. As the cows produce the manure, it is automatically scraped into a large pit by “ally scrappers”, or large blades attached to cables (only applicable in free-stall dairy barns). Once the manure is in the pit, it undergoes anaerobic digestion, where large quantities of naturally occurring bacteria break it down into methane gas, liquids, and solids.
After digestion, the solids left behind are a dry and sterile, sawdust-like material that can be used as bedding for the cows. This alternative for bedding eliminates the need for buying large quantities of sawdust which lend to the destruction of forests, and also eliminates another expense for the farm. While the cows use this natural bedding, it eventually becomes pushed back into the ally-way where it gets scraped back into the pit with the rest of the manure, is digested again, and is recycled.
The liquid of the anaerobic digestion is full of nutrients. It is taken and applied to the farm’s crops, including the algae, as a natural fertilizer. This cuts farm costs further by lessening the need to purchase fertilizer, and boosts the production of the crops that feed the cows, and are sold on market for human consumption, whilst concurrently, supplies the nutrients that are needed to grow the algae that starts the cycle over again.
The process involving the acquisition of methane gas that is released in the anaerobic digestion is one of the most important steps, because the gas is collected as it is released, instead of allowing it to escape into the atmosphere as a greenhouse gas. The methane gas that is collected is used to power several efficient biogas turbines. These turbines, in turn, are used to power generators that supply green power for the entire farm, and the surrounding electric grid. A portion of the methane is also burned directly by the farmer to dry his crops, and to heat the farm’s buildings. This eliminates the farm’s largest expenses of electricity and heating costs, and since the farm is supplying more electricity then it is using, the farm is paid for the electricity.
All electrical functions would be backed up by wind turbines, solar panels, and, as a last resort, the electric grid that the farm is a part of. Also, since CO2 is an essential growth factor in producing algae, the exhaust that is produced by the biogas turbines is saved, routed to, and bubbled up through the algae growth tubes where it will be reabsorbed by the algae plant, and is reused in the biodiesel.
In utilizing and integrating these processes on the farm, I believe I will be able to effectively make my family’s farm completely self-sufficient, and environmentally friendly while producing zero net emissions. This achievement is possible because all the CO2 produced by the farm’s buildings, machinery and products, was previously extracted out of the atmosphere, and will not contribute to the build up of CO2, as the traditional burning of fossil fuels would have. This becomes very important since it is thought that agriculture produces around the same amount of greenhouse gases as transportation.
Information on biodiesel.
http://www.srsengineering.com/asv_series.html
Information on a potential algae production design.
http://www.algaelink.com/index.html
Information on anaerobic digestion.
http://www.adelaide.edu.au/biogas/anaerobic_digestion/
Information on microturbines.
http://www.microturbine.com/prodsol/solutions/secure.asp
Information on the energy crisis.
http://www.futurecrisis.com/alternative-energy-plans-4.php