In this dissertation, we propose a novel distributed approach to the control of generators in the electric grid. Specifically, we consider the problem of the optimal economic dispatch of generator; we present a simple, distributed algorithm, which adjusts the power-frequency set-points of generators to correct for power imbalances arising from generation and load fluctuations. In this algorithm each generator independently adjusts its real-power output based on its estimate of the aggregate power imbalance in the network; such as an estimate can be independently obtained by each generator through local measurements of the frequency deviation on the grid. Eventually, over the course of network operation, the distributed algorithm achieves the equal-marginal-cost power allocation among generators while driving the power imbalance exponentially to zero. In the absence of power losses, we prove the eventual optimality of the distributed algorithm under mild assumptions (strict convexity and positivity of cost functions) and present simulation results to compare its performance with traditional (centralized) dispatch algorithms. Furthermore, we present numerical simulation results that show that the distributed algorithm performs well even in the presence of power losses and other constraints. We argue that distributed control methods are especially attractive for electric grids with smart meters and other advanced capabilities at the end node and grids with high penetration of alternative energy generators and we identify interesting open problems for future work in this area.

Microalgae are a rich, largely untapped source of lipids. Algae are underutilized, in part, because lipid formation generally is stimulated by stress, such as nutrient deficiency. Nutrient deficiencies reduce growth, resulting in a tradeoff between elevated cellular lipids and abundant cell division. This tradeoff is not well understood. We also have a poor understanding of the physiological drivers for this lipid formation. Here we report on three sets of research: 1) Assessment of species differences in growth and lipid content tradeoffs with high and low level nitrogen deficiency; 2) Investigation of physiological drivers of lipid formation, by mass balance accounting of cellular nitrogen with progressing deficiency; 3) Examination of the effects of sodium chloride and silicon on lipid production in a marine diatom. 1) Nitrogen deficiency typically had disproportionate effects on growth and lipid content, with profound differences among species. Optimally balancing the tradeoff required a wide range in the rate of nitrogen supply to species. Some species grew first and then accumulated lipids, while other species grew and accumulated lipids concurrently--a characteristic that increased lipid productivity. High lipid content generally resulted from a response to minimal stress. 2) Commonalities among species in cellular nitrogen at the initiation of lipid accumulation provided insight into the physiological drivers for lipid accumulation in nitrogen deficient algae. Total nitrogen uptake and retention differed widely among species, but the ratio of minimum retained nitrogen to nitrogen at the initiation of lipid accumulation was consistent among species at 0.5 ± 0.04. This suggests that lipid accumulation was signaled by a common magnitude of nitrogen deficiency. Among the cellular pools of nitrogen at the initiation of lipid accumulation, the concentration of RNA and the protein to RNA ratio were most similar among species with averages of 3.2 ± 0.26 g L-1 (8.2% variation) and 16 ± 1.5 (9.2% variation), respectively. This implicates critical levels of these parameters as potential signals initiating the accumulation of lipids. 3) In a marine diatom, low levels of either sodium chloride or silicon resulted in at least 50% increases in lipid content. The synergy of simultaneous, moderate sodium chloride and silicon stress resulted in lipid content up to 73%. There was a strong sodium chloride/silicon interaction in total and ash-free dry mass densities that arose because low sodium chloride was inhibitory to growth, but the inhibition was overcome with excessive silicon supply. This suggests that low sodium chloride may have affected metabolism of silicon.

<p>In Malawi 2.5 % of the forest disappears each year. The use of firewood and charcoal, deriving from forest resources,</p><p>accounts for about 99 % of the household energy demand in Malawi and is a cause to the deforestation. The Government of</p><p>Malawi recently launched a programme called Promotion of Alternative Energy Sources Programme (PAESP) with the aim</p><p>to reduce the use of firewood and charcoal. One of the fuels included in the programme is the biomass briquette. The aim</p><p>with this study is to evaluate the viability of biomass briquettes as a sustainable alternative energy source to firewood and</p><p>charcoal for households in Malawi.</p><p>Research for the study was carried out during three months in Malawi. Visits were made to a number of briquette</p><p>production sites to study the manufacturing methods and to collect briquette samples. The briquettes were tested using</p><p>various methods and then compared with results for firewood and charcoal.</p><p>At the moment various production methods are used in Malawi, with a high difference in technical complexity and cost.</p><p>Machines produced from wood using very basic mechanics can apply similar pressure as more advanced metal pressers.</p><p>They also seem to be better suited than those made of metal, in terms of price and availability.</p><p>The majority of the briquette producers in Malawi use waste paper as base material. Although the paper briquettes are good,</p><p>other raw materials will be needed if the production is supposed to be significantly increased.</p><p>The briquettes burn well using the most common stoves in Malawi, including the commonly used charcoal stove. While</p><p>firewood is cheaper to use than other available fuels, the briquettes seem to be able to compete with the fuel costs for</p><p>charcoal.</p>

In this research project, adsorption is considered in conjunction with the reverse water gas shift reaction in order to convert CO2 to CO for synthetic fuel production. If the CO2 for this process can be captured from high emitting industries it can be a very good alternative for reduced fossil fuel consumption and GHG emission mitigation. CO as an active gas could be used in Fischer-Tropsch process to produce conventional fuels. Literature review and process simulation were carried out in order to determine the best operating conditions for reverse water gas shift (RWGS) reaction. Increasing CO2 conversion to CO requires CO2/CO separation downstream of the reactor and recycling unreacted CO2 and H2 back into the reactor. Adsorption as a viable and cost effective process for gas separation was chosen for the CO2/CO separation. This was started by a series of adsorbent screening experiments to select the best adsorbent for the application. Screening study was performed by comparing pure gas isotherms for CO2 and CO at different temperatures and pressures. Then experimental isotherm data were modeled by the Temperature-Dependent Toth isotherm model which provided satisfactory fits for these isotherms. Henry law’s constant, isosteric heat of adsorption and binary mixture prediction were determined as well as selectivity for each adsorbent. Finally, the expected working capacity was calculated in order to find the best candidate in terms of adsorption and desorption. Zeolite NaY was selected as the best candidate for CO2/CO separation in adsorption process for this project. In the last step breakthrough experiments were performed to evaluate operating condition and adsorption capacity for real multi component mixture of CO2, CO, H2 in both cases of saturated with water and dry gas basis. In multi components experiments zeolite NaY has shown very good performance to separate CO2/CO at low adsorption pressure and ambient temperature. Also desorption experiment was carried out in order to evaluate the working capacity of the adsorbent for using in industrial scale and eventually temperature swing adsorption (TSA) process worked very well for the regeneration step. Integrated adsorption system downstream of RWGS reactor can enhance the conversion of CO2 to CO in this process significantly resulting to provide synthetic gas for synthetic fuel production as well as GHG emission mitigation.

Immobilization of photosynthetic cultures has been used to generate biofuels and high value compounds through direct conversion of CO2 and water using sunlight. Compared with suspended cultures, immobilized bacteria can achieve much higher densities resulting in greater areal productivity. Limitations exist however, on the density that can be reached without compromising access to light and other nutrients. In this thesis an optofluidic approach to overcoming the challenge of light delivery to high density cultures of cyanobacteria is described and proof of concept experiments presented. This approach uses optical waveguides to deliver light to cells through bacterial interaction with the evanescent field and is tailored to meet each cell's need for light and nutrients. Experiments presented here demonstrate biofilm proliferation in the presence of evanescent fields. Illumination of surfaces by surface plasmon enhanced evanescent fields is also shown to be an effective and potentially useful technique to grow biofilms within optofluidic architectures.

Abstract: How to secure the power supply for future generation vehicles is an open question. This thesis uses Web-HIPRE as a tool of Decision Support System to predict the main compositions of future generation vehicles and also analyzes the advantages and shortages of currently existing solutions. The method of system approach is utilized to find out common problems of those existing solutions and to form an integrative solution. A model for this integrative solution is built under PowerSIM environment and the main objective of the model is to simulate the energy balance between power supply and demand. Finally, a brief discussion mainly focuses on the social and economic impact of the solution is made under PEBOSCA framework.

The global climate anomalies lead to significant disaster. Governments have attached great importance to develop related strategies. In 2009, climate change conference were held in Copenhagen, which gathered 194 representatives of member states to discuss the next phase in response to climate changing. The United States, China and other nation¡¦s leaders attend this conference, which shows the importance of the meeting. On the other hand, corporates started to focus on the green energy technology. On business efficiency and competitiveness, the enterprises for the timely introduction of green energy technology, may be able to provide better production and manufacturing. However, for enterprises to import new technology is often associated with high costs and high risks. Therefore, imported green energy technology has become a very challenging task. For the solar industry, as oil prices coupled with the rise of environmental awareness. The solar industry growth can be expected. Therefore, this study design AHP (Analysis Hierarchy Process, AHP) questionnaire for experts and scholars, government agencies and related companies conducted a questionnaire survey. Developing a general framework for evaluating and introducing solar energy technology into a technology company is presented. The results showed that a lot of experts put great emphasis on the gradual trend of green production. Cost criterions are also as the key consideration for those companies to import solar installation. For example, they consider the implementation costs and maintenance costs when those companies need to introduce solar energy equipment. Most important part is the policy criterion which is the key consideration for those companies. In the future, we need more experts and scholars, government agencies and related companies to do more efforts and promotion to this industry.

The Government of India has an ambitious mission of ¡¥power for all by 2012¡¦. This mission would require that the installed generation capacity should be at least 200,000 MW by 2012 from the present level of 114,000 MW. To be able to deliver this power to the entire nation, an expansion of the regional transmission grid-network and inter regional capacity to transmit power would be essential. The latter is required because resources are unevenly distributed in the country and power needs to be transmitted through great distances to areas where load centres exist. Indian government¡¦s ambitious plan can be met. Power generation is one thing but distribution and last mile delivery is a real challenge in remote rural India. 70% of India still lives in such rural settings. India is also notorious for loss of power in distribution due to its out dated distribution infrastructure and mismanagement. A lot is being done to improve the situation however to fast remedy the problem; government and private players can play an important role in setting up small power plants that are based on eco-friendly and efficient mode of power generation. India¡¦s western states and North eastern states are rich in natural gas. Unfortunately these areas are also remote, especially the North Eastern sector. Delivering power is quite a challenge. In search for a solution to this challenge we could be wise to choose greener solutions than otherwise. In the quest of which solution would be suitable for the chosen project, one could look across an array of available conventional and non-conventional sources of energy. Utilizing the locally available natural gas would be a right strategy. It also suits as a green choice. To exploit the availability of natural gas we would need technologies that are of right scale and are easily executable. A multi-million dollar mega gas power generation plant is neither plausible nor executable in those rural settings; however something of a smaller scale could be a good fit. There we see an opportunity for a green technology that may work wonder. Taiwan based Green Power Engineering Corporation has a solution in the form of their cutting edge gas turbine generator. With ease of setup and efficiency coupled with eco-friendly technology, the Gas turbine generators has the potential to be the solution to the much needed rural development by providing them continuous power.

We analyze four alternative energy mutual funds using a multi-factor capital asset pricing model with generalized autoregressive conditionally heteroskedastic errors (CAPM-GARCH). Our findings will help portfolio managers and others who seek to predict the return on investment in alternative energy firms. We find that alternative energy firms tend to be riskier than the general US stock market, have a low, but significant and positive response to oil prices, and have a significantly high and negative response to the value of the dollar relative to other currencies. Our results also suggest that alternative energy firms should hedge against currency exchange rate fluctuation.

On November 7, 1973, President Nixon asked Americans to lower their home thermostats to a national average temperature of 68 degrees. On February 2, 1974, over half of the gas stations in the New York City area closed after selling out of fuel. These and other restrictions resulted from the Arab oil embargo of 1973-1974, a pivotal event in American history that made residential energy conservation an immediate national imperative. This dissertation situates American housing within the ecologically-oriented 1970s, when energy independence and environmental protection became political and popular priorities. I study two California communities that shared geographical and temporal proximity but responded to the energy crisis with divergent approaches to the ideal of energy-conserving, healthy housing. Part I explores early indoor environmental research at the Lawrence Berkeley Laboratory. In collaboration with utility companies, homebuilders, and homeowners, Berkeley’s researchers studied how residential energy conservation affected indoor air quality (IAQ) in conventional and alternative homes. Their goal was finding the “optimal balance” between equally vital goals: energy conservation, healthy indoor air, and cost-effectiveness. By the early 1980s, IAQ was the leading criterion in national conversations about healthy housing. Part II explores owner-built housing in 1970s California. Owner-builders embraced environmentalism and voluntary simplicity. Like Berkeley’s scientists, they pursued residential energy conservation, but did this either by living in minimalist cabins without heat or electricity,or by using alternative technologies (solar power, earth-building). Their top priority for housing was autonomy, not IAQ. They campaigned for the right to build their own low-cost housing unconstrained by building codes. They prioritized personal and planetary health in designing and building their homes, arguing that a healthy house was an instrument of social and environmental change. In juxtaposing these two approaches -- one academic and quantitative; the other holistic and iconoclastic -- I show that healthy housing has been a flexible ideal shaped by competing priorities: energy, health, affordability, and environmentalism. Housing, the fundamental link between people and the outdoor environment, is an ideal focus for environmental historians and adds another dimension to knowledge of American history since the energy crisis. / History of Science