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2 October, 2008
The biofuels is combustible derived of alive beings or of the waste that these produce. These include Solids (Wood, straw, etc.), Biogas from excrements/waste, and Liquids (bioethanol, biobuthanol, biodiesel, etc.) derived of the compounds of the plants (starch, lignocellulose, oils, etc.). Based in this definition the biofuels has been used for centuries, a lot before the petroleum became the main source of the element carbon (C) in our lives.  To these in english are referred the 6 F; “Food, Fuel, Feed, Feedstock, Fertilizer, Fiber”. All these contain the coal element in their chemical structures. This implies that the debate of the biofuels (“Food versus Fuel”) is much more complex and has to include the other remaining F. This complexity points to that any strategy of the agricultural sector that is interested to implant in Puerto Rico HAS to consider crops able to assist multiple sectors. The agriculture will become the primary raw material source for the carbon derived products. Also, the use of the land will compete with other basic necessities and potential uses as residences, ecological reservations, free-time places and entertainment, commercial/industrial establishments and energy generation by means of sustainable energy technology. Not less important are the supplies and necessities of waters for all these sectors which adds another level of complexity to this discussion. Based on the above-mentioned some strategies for the installation of this technology in Puerto Rico can be concluded and recommended: 1) First, there is not a magic wand, divine harvests or unique strategy that will be able to solve all or not even one of our necessities. All the proposed solutions should consider and integrate not only their technical aspects but also the social and economic and social dynamics. 2) Puerto Rico should consider the model of the Regional Biorefineries in its strategies. The Biorefineries are facilities that integrate processes and equipments to convert the biomass into multiple products, for example: foods, fuel, power and chemists. It is basically a refinery except that instead of using petroleum as raw material it would use all the components of the agricultural plants as carbon sources. This includes the leaves and stems that is known as lignocellulosic material the same as the sugars and starches that would be used for the food. At the moment, of each 5 pounds of crop only 1 to 2 are used for food, the rest is lignocellulosic biomass that can be processed in a biorefinery. 3) The crops that are chosen should not only assist the necessities of the 6 F, but they should also have high productivities. The microalgaes is a vegetable species that is able to satisfy some of these requirements. For example, its growth and chemical products production surpasses any terrestrial crop by factors bigger than 20. These studies were carried out by the National Renewable Energy Laboratory (NREL) of the Department of Federal Energy in the 1980-90 under the “Aquatic Species Program”. The investigation in this area has resurged and in Puerto Rico, the RUM has an initiative in the Agricultural Experimental Station of Lajas to study the microalgaes in open ponds and the biorefinery concept. 4) All this requires an integral plan of land and water handling that it is able to not only diminish the existent vulnerability, dependence and addiction to the petroleum derived fuels but rather in turn assists vulnerabilities of eatable products and raw materials for the industrial sector.   Oceanic energy The oceanic energy is another of the renewable energy alternatives that is bieng discussed in these moments not only in Puerto Rico but around the world. The best known and developed technologies are the generators of energy by means of waves, tides, submarine currents and thermal ocean (well-known as OTEC for their initials in English). Other less well-known ones intend to use the gradients or differences in the salinity (osmotic pressure) and carbon dioxide (CO2) between the surface and the big depths. This last one is based on the difference of density or “head” caused by the difference in concentration of this gas in the water between the surface and the bottom. Puerto Rico, for being an island, has places that have been identified as of high potential for the installation of these technologies. Studies in the RUM demonstrate that in Puerto Rico the energy of the tides and of the currents is not cost-effective to produce electricity nowadays with the available technology and for the low resource that we possess of these . Between OTEC and the energy of the sea waves to produce electricity, the technology of the sea waves is ahead than OTEC with prototypes in several countries (United States, Japan, Portugal, Spain) and commercial outlines in administration (United States, Portugal). Also, there is enough resource of sea waves to produce electricity in Puerto Rico, both with devices buoy type as with devices in the coast. The most cost-effective are those buoys type and at the moment there are studies being carried out in the RUM to quantify the cost for kWh. Punta Tuna in the southeast of the Island, is one of the best places in the world to use the thermal oceanic energy due to the depth that the sea has near that place. That proximity would facilitate its construction and it would diminish the investment costs. These studies were carried out more than 25 years ago, they were abandoned and now they are intended again as energy alternative (the Authority of Electric power is in negotiations to establish one of these facilities). However, the most advanced oceanic technologies are not commercially mature. In fact, many of them are in the evaluation of prototypes stage. Also, all these technologies, the same as the non-oceanic ones, impact somehow or other the coasts, their echo-systems and the use of the area for other activities. It is important that these effects are identified and that theyare incorporated in the technical, economic and social viability analyses. Another challenge for all these systems is the saline atmosphere of the coasts. This implies that the selection of materials and their cost are critical and that it is necessary to be extremely cautious in the estimate of the operational costs since the maintenance of these units can be significant. Besides the corrosive effects of the salinity, the biological growth in the surfaces known as “biofouling” can be more destructive than the effects of the salinity. In conclusion, both the Biorefinery and the Oceanic Energy are two options that possess characteristic that should be seriously considered not only in energy aspects but rather they assist other basic necessities. The discussion of these options, the same as other proposed renewable strategies by the complex nature of the problem, should include an early, wide, inclusive and transparent discussion if they want to be sustainable strategies and of long term benefit in Puerto Rico. In May of 2008 a dialogue began about biofuels in the UPR-RUM organized by the Tropical de EnergÃa Ambiente y Sociedad (ITEAS). This university dialogue seeks to expand out of the RUM, and it is presented as a space to take this discussion to actions and concrete strategies, multisectorials to develop or to adapt these technologies to the Boricua environment.  Dr. José Colucci RÃos, PE*/Special for Claridad * The author is Professor and Investigator on Sustainable Energy, UPR-RUM, ITEAS, Dean Associated of Investigation and Development in Engineering, UPR-RUM and Coordinator of the Program of the Fundación Sloan in InQu-UPR-RUM. Source: Claridad Puerto Rico Deje un comentario |
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