ENGG 413 Sustainable Energy Management PDF

ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Sustainable Energy Management Introduction Renewable energy will be discussed, along with their examples in the Philippines. Moreover, concerns regarding and the factors affecting energy manageme...

ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Sustainable Energy Management Introduction Renewable energy will be discussed, along with their examples in the Philippines. Moreover, concerns regarding and the factors affecting energy management of a country will also be tackled. Learning Outcomes Intended Learning Outcomes 2 and 3 (Syllabus) ILO 2 - Identify the various effects of environmental pollution and describe the engineer's role in the manipulation of materials and resources. ILO 3 - Select appropriate design treatment schemes and efficient safety measures for waste disposal and explain their effect if implemented in the community and in the workplace. Topic Outcomes: ​Describe renewable energy resources and determine the advantages and disadvantages of each type Solar Energy - conversion of sunlight into usable energy forms. Solar photovoltaics (PV) and solar thermal electricity are well estaSun radiation arrives outside the Earth with a specific spectral distribution, which is modified throughout the atmosphere until reaching the Earth’s surface. - The amount of solar energy available on a given location of the earth differs depending on the Geographic latitude Time of day Year Solar radiation components Direct radiation​ - radiation from the sun that reaches the Earth without scattering. As it is the only one with a known vector (solar vector), it can be concentrated using technological devices 1|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Diffuse radiation​ - radiation that is scattered by the atmosphere and clouds Established Solar Technologies Solar PV Solar Thermal Directly converts solar energy to electricity Harnessing solar energy for thermal applications – domestics, industries, hotels, hostpitals, leisure, etc., Absorbs 80% incident solar radiation but Use thermal energy for space heating, fluid convert only small portion to electricity and generate electricity Release excess heat during the operation Has been accepted worldwide as solar thermal power Different Solar Thermal Technologies - A solar thermal collector converts solar radiation into useful heat and its performance depends both on optical and thermal features. 1. Parabolic Trough Solar Thermal System​ - The troughs concentrate sunlight onto a receiver tube that is positioned along the focal line of the trough. Example: SEGS in California, with 936,384 mirrors 2. Central Tower Solar Thermal System​ - system takes advantage of numerous heliostats to reflect sunlight onto the surface of the high-temperature heat absorber on the top of the center tower. The fluid medium (water, fused salt or air) is heated, thus directly or indirectly generating overheated steam or high-temperature air to propel the generating set. Example: Ivanpah 440 MW Power Facility, California, 214,000 heliostats 3. Linear Fresnel Solar Thermal System​ ​– one-axis solar tracking device, with the parola divided into many small nearly flat mirrors with independent movement, simultaneously focusing the linear absorber located in optical focus. E :Murcia, Spain with 100MW/km2 land use 4. Parabolic Dish Solar Thermal System​ ​– heliostats with sunlight focused on the engine with a cavity receiver on the focal point. One of the most efficient solar 2|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy electric technologies. Example: Arizona, US 5. Flat plate solar collectors​ –​ mostly used in heating water for showers. Example: small-scale than other examples, used in heating water in swimming pools and showers *Heliostats – two-axis tracking mirrors which concentrate solar radiation maintaining the reflected image at fixed position over the course of the day. Solar Collector Source: Wimmer et al. (2015) Solar photovoltaics - advantage: Module manufacturing is being done in large plants, which allows for economies of scale, and it can be deployed in very small quantities at a time - disadvantage: As PV generates power from sunlight, power output is limited to times when the sun is shining. However, a number of options (demand response, flexible generation, grid infrastructure, storage) exist to cost-effectively deal with this challenge. Biomass Energy - burning of wood, bark, branches, starchy roots, manure and other plant and animal materials to produce energy 3|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy - An example of this is ​San Carlos Biopower Inc. in Negros Occidental,​ which uses agricultural wastes such as sugarcane trash, coconut husks and shells, woods, grasses and other energy crops from nearby dedicated plantations as feedstock. - Denmark, the energy-independent islands of Samsø and Ærø get some of their space heating from biomass, both from agricultural wastes (such as straw) and biomass crops Biomass Energy Conversion Process Source: Energy Company Numbers, 2020 - Heat generated by burning biomass in a boiler is used to produce steam. This steam is used by a steam turbine which drivers a generator to produce electricity - Other methods for turning biomass into fuel are shown below: 4|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Source: Cunningham and Cunningham, 2012 Hydropower - falling water produces energy which is harnessed as a valuable contribution to total energy supply. - To produce energy to power a country, dams are built. However, they can have unwanted social and environmental effects, such as drought to the other side of the dam, endangering freshwater biodiversity thus having impact in the fishing industry, and displacement of communities. - Example in the Philippines: Maria Cristina Falls and Agus VI Hydroelectric Plant, supplying 200 MW of electricity 5|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Source: Project Lupad, 2016 - Less destructive alternatives to dams are low-head hydropower technologies, and using high-efficiency turbines that can operate on run-of-the-river flow Wind - Wind energy comes from capturing kinetic energy using turbines to generate electricity, and can be onshore or offshore. - In earlier times, windmills were used to pump water in farms and ranches. - Example in the Philippines: Pililla Win Farm in Rizal, supplying 54 MW to Meralco 6|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Source: “Pililia Wind Farm.png” ​by ​Rmnsantiago​ is licensed under ​CC BY-SA 4.0 - Potential for wind energy in the Philippines can be found on the redder parts of the map below 7|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Source: World Bank Group, 2019 Sustainable Energy Energy is the main driver of every nation’s economy, and what one chooses as their sources has global environmental and financial effects. This is why “most important questions in environmental science have some link to energy resources—from air pollution, climate change, and mining impacts, to technological innovations in alternative energy sources (Cunningham and Cunningham, 2012).” Renewable and non-renewable are our options as energy sources. Non-renewable sources, coal, oil and natural gas, cannot be relied on fully because of their effects on global temperature. However, it is also not possible to be powered by 100% renewable energy (RE) without relying on non-renewables (NRE) in the first decades of the plan. For example, Denmark targets to use 100% RE in energy and transport sectors by 2050. In 2015, they are producing 43% RE; in 2017 28.6% of their energy was still produced by NRE, and they projected to eliminate coal from power production by 2030 (Ortis and Spigonardo, 2015). Thus, to have a sustainable energy management system, one must have a good balance of RE and NRE in their energy mix. 8|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Energy Mix refers to how final energy consumption in a given geographical region breaks down by primary energy source. To meet its energy needs, each country uses the energy available to it, in different proportions. While it varies significantly from one country to another, globally fossil fuels account for over 80% of the energy mix. WHY A MIX? For each region or country, the composition of the energy mix depends on: The availability of usable resources on its territory or the possibility of importing them The extent and type of energy needs to be met Policy choices determined by historical, economic, social, demographic, environmental and geopolitical factors Data Source: Bunye, Cruz, Marcelo and Tenefrancia, 2020 Renewable Energy (RE) in the Philippines 9|Page ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Hydropower Geothermal Biomass Solar, wind, ocean Biofuels – alcohol in diesel; jathropa In comparison, here is the energy mix of South Korea and Germany in 2018: (Maennel, Kim, 2018) The Philippines has higher energy production using coal than the 2 countries mentioned above. Moreover, they both use nuclear power in their mix. Major constraints need to be addressed in pursuing RE in the Philippines: (i) insufficient fiscal and financial incentives; feed-in tariffs (ii) absence of commercially viable market for RE systems; and, (iii) relatively high cost of technology 10 | P a g e ENGG 413 ENVIRONMENTAL SCIENCE AND ENGINEERING Main Topic 4: Sustainable Development and Energy Sustainable Energy Management Life Cycle of Energy Systems - help determine environmental burdens from cradle to grave Taking a look at PV, Wind and Coal, different stages of the life of the systems release different percentages of carbon dioxide equivalents. LIFE CYCLE UPSTREAM OPERATIONAL DOWNSTREAM STAGES PROCESSES PROCESSES PROCESSES Photovoltaics (PV) System Plant Power Generation System/Plant Component System/Plant Decommissioning Manufacture Operation and Disposal Installation/Plant Maintenance Construction ~40 g CO​2​e/kWh 60%-70% 21%-26% 5%-20% Wind Raw Materials Power Generation Power Plant Extraction System/Plant Decommissioning Construction Operation and Waste Disposal Materials Maintenance Manufacture Transmission Lines ~35 g CO​2​e/kWh 95% 5%