Engineering Commons^™

Reflexions On The Use Of Renewable Power Sources And Nuclear Energy In Portugal, João F. Gomes

João F Gomes

This paper analyses the current energy balance of Portugal, considering the actual sources which are mainly traditional fossil fuels, hydroelectric power and renewables. Other potential sources are discussed also and taken into consideration in view of the previewed evolution of the country in energetic terms. Among these, nuclear power, once regarded as an option, is now being re-considered. This paper also sums up the main issues to be considered in a future debate on the subject.

A Hybrid Reconfigurable Solar And Wind Energy System, Sagar A. Gadkari

ETD Archive

We study the feasibility of a novel hybrid solar-wind hybrid system that shares most of its infrastructure and components. During periods of clear sunny days the system will generate electricity from the sun using a parabolic concentrator. The concentrator is formed by individual mirror elements and focuses the light onto high intensity vertical multi-junction (VMJ) cells. During periods of high wind speeds and at night, the same concentrator setup will be reconfigured to channel the wind into a wind turbine which will be used to harness wind energy. In this study we report on the feasibility of this type of …

Experimental Test And Cost Analysis Of Residential Solar Water Heaters, Sai Mahesh Dharanikota

ETD Archive

Non renewable energy sources have been diminishing in the recent times.Renewable energy is abundant in nature, but the use of it is very low.Lowering the energy consumption and using renewable energy, thereby decreasing the use of fossil fuels and nuclear energy would have a positive impact on our environment. The use of solar energy as an alternate resource is discussed in this research. The solar water heater is tested for its recovery rates, under normal solar radiation in static testing. The effect of solar radiation in increasing the temperature of water is studied and discussed. The solar water heater is …

Biomass And Biofuels In Maine: Estimating Supplies For Expanding The Forest Products Industry, Jonathan Rubin, Kate Dickerson, Jacob Kavkewitz

Energy & the Environment

This paper estimates the renewable energy potential of Maine’s forest resources, and how much energy these resources could potentially provide the state. Using the most recent state-specific data available, and a methodology similar to the Billion Tons Report, we find that ethanol production from Maine’s forest residues could potentially provide 18% of Maine’s transportation (gasoline) fuels with a fermentation wood to ethanol process. Making Fischer-Tropsch diesel (F-T diesel) using forest residues can replace 39% of Maine’s petro-diesel consumption. Actual levels of biofuels that can be produced will depend on conversion factors and forestry residue removals that are subject to uncertainty.

Thermal Performance Of Low Approach Evaporative Cooling Systems In Buildings, Ben Costelloe, Donal Finn

Conference Papers

Meteorological enthalpy analysis of temperate and maritime climates above 45˚N suggests that the water-side evaporative cooling technique has considerable unrealised potential with contemporary "high temperature" building cooling systems - such as chilled ceilings. As low approach conditions are the key to exploiting the cooling potential of the ambient air, thermal performance at such conditions needs to be investigated. To address the research issues a test rig, based on an open cooling tower and plate heat exchanger and designed to maximise evaporative cooling potential, has been constructed at DIT. A combination of experimental measurement and analysis is used in the investigations. …

Catalyzing Mass Production Of Solar Photovoltaic Cells Using University Driven Green Purchasing, Joshua M. Pearce

Joshua M. Pearce

Thermal Efficiency Characteristics Of Indirect Evaporative Cooling Systems, Ben Costelloe, Donal Finn

Conference Papers

Recent developments in enhancing heat transfer in cooling towers, together with the success of chilled ceilings, have prompted a review of the evaporative cooling technique. in temperate maritime climates. The thermal efficiency of such systems is a key parameter, as a measure of the degree to which the system has succeeded in exploiting the cooling potential of the ambient air. This paper presents the results of experimental research into the thermal efficiency of a water-side open indirect evaporative cooling test rig designed to achieve low (1-4 K) approach conditions. Secondary efficiencies in the range 0.24-0.76 have been achieved.

Developments In Evaporative Cooling Of Buildings In Maritime Climates, Ben Costelloe, Donal Finn

Reports

Concern with environmental emissions has focused attention on traditional forms of energy use in buildings, with a view to reducing and making more rational use of energy consumption. One area of concern is the traditional, refrigeration based, commercial air conditioning system, which has high levels of electrical power consumption in fans and refrigeration compressors. There is also concern among building owners and design teams, supported by the PROBE series of post occupancy studies, conducted by the CIBSE, that many buildings, with traditional forms of air conditioning, under perform in terms of occupant satisfaction, ease of operation and control, maintenance costs …