Power generation from geothermal resources : challenges and opportunities

Thesis (S.M.)--Massachusetts Institute of Technology, Technology and Policy Program; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2000.Includes bibliographical references (leaves 73-79).As we enter the 21st century, increasing concerns about global warming have stimulated an upsurge of interest in the use of non-fossil energy technologies for electricity production. As a result there is an opportunity for expansion of geothermal resource development. This thesis examines power generation technology for two distinct categories of geothermal resources: Hydrothermal and Hot Dry Rock (HDR). The thesis assesses growth opportunities for, and challenges to, the full deployment of geothermal power systems in the electricity market. It analyzes the key impediments that - have and will affect the attractiveness of geothermal technologies, describes policy measures that can be adopted to overcome these impediments, and draws conclusions and recommendations for R&D on geothermal systems.by Olga Kitsou.S.M

The role of technology in the water–energy–food nexus. A case study: Kerinthos, North Euboea, Greece

The water–energy–food (WEF) nexus is a basic element of prosperity, yet it is not equally distributed on the land. Human progress has optimized the function of the WEF nexus to bridge the inequality gap. In order to understand this progress, this study compares the preindustrial and modern agricultural practices in an area in Greece. Interviews were conducted with an elderly man who lived in the 1950s, and the process was quantified in units of WEF. The same procedure was also carried out with modern farmers for modern agricultural practices. In comparing the past and present agricultural processes, it is observed that today, a farmer can feed approximately 100 times more people. This feat has been achieved as modern practices push the land with energy sources in multiple ways (fuels and fertilizers). However, energy indices such as energy ratio, net energy gain, specific energy, and energy productivity do not seem to be improved. Furthermore, farmers prefer to pump underground water for irrigation, instead of utilizing the nearby river, as was done in the past when the river provided both energy to the watermill and an abundance of water for irrigation. In addition, as the price of wheat is dependent on the stock market, even in 2023, there are risks to food security, the cultivation of wheat was not economically efficient for farmers in this area in 2023