Global Energy Consumption: Trends and Alternatives
UNIT 3 INTRODUCTION
Energy consumption is thirty times higher than a century ago. This growth necessitates developing new techniques to enhance the exploitation of existing sources and gradually replace non-renewable ones showing signs of depletion. The goal of developed countries should be the effective and rational use of energy to secure future resources.
HISTORY OF POWER CONSUMPTION
In studying evolution, two variables must be considered: primary energy consumption and transformed (secondary) energy consumption. The most common are coal, petroleum, hydropower, natural gas, and nuclear energy. Since the 1950s, the use of coal has decreased, while natural gas has increased.
Oil is crucial in the global energy supply. However, since 1973, due to significant price increases, consumer countries have embarked on energy-saving and substitution plans. Transportation depends almost exclusively on this source. The Organization of Petroleum Exporting Countries (OPEC) controls the international oil market, holding 70% of world reserves.
Natural gas use is increasing due to its high calorific value, clean burning, ease of use, and versatility.
Hydropower is the only renewable energy source present (6% of production), but its use presents difficulties as it requires abundant and regular flow, increasing production costs.
Nuclear energy is the most recent energy source. In 1989, it represented 5.4% of primary energy. Electricity production comes from any of the above primary sources, although coal and oil derivatives are used less due to economic and environmental reasons, with natural gas and nuclear energy gaining prominence.
ENERGY CONSUMPTION IN SPAIN
Evolution of Energy Needs
Spain lags behind developed countries like the USA and the UK. The energy landscape has changed substantially due to increased demand driven by economic development and the use of nuclear, natural gas, and alternative energy sources.
Foreign Energy Dependence
Spain is energy-dependent, with a dependency degree exceeding 60%, indicating an energy deficit. The dependence degree can be determined by the expression: (CIB – GDP) / CIB (in %), where CIB is Gross Inland Consumption (million toe = ton oil equivalent, 1 toe = 41.84 x 109) and GDP is Gross Domestic Production (million toe).
Coal
Spain has assured domestic supplies for about 250 years (1450 million tonnes in 1990). However, imports are necessary due to extraction costs and low heat output. Reserves are concentrated in Asturias, León, La Coruña, and Teruel.
Oil
Reserves are negligible (2.6 million tonnes). Crude imports decreased from 51.4 million tonnes in 1993 to 29.5 million tonnes in 1998 due to petroleum energy production, mainly for the automotive sector.
Hydroelectricity
The main difficulty was transport development (electricity was direct current, limiting long-distance transport). The advent of AC generators enabled transport development, but hydroelectricity production has declined due to nuclear and petroleum-fueled power plants. Spain has one of the most developed hydroelectric parks globally. Plants are located in watersheds with higher rainfall and flow (Tajo, Duero, Ebro, and the North), with a stored water capacity exceeding 60% of total production capacity. Electricity production through hydroelectric plants depends on wetland filling, rainfall, and water needs for human supply and agricultural irrigation.
Natural Gas
Spanish gas production is low (20%), with imports mainly from Algeria and Libya. Energy policy promotes increased gas supply. A long-term agreement with Algeria led to the creation of pipelines connecting to Algeria via Morocco. Three regasification plants are located in Barcelona, Cartagena, and Huelva.
Nuclear Energy
Nuclear fusion requires uranium. Spain’s proven uranium reserves amount to 39,000 tonnes (enough for over 40 years), placing it second in Europe behind France. Nuclear power is used only for electricity production.
Electricity Production
Electricity production has increased since the first hydroelectric plants due to the incorporation of steam turbines for thermal power production, nuclear power plants, and the installation of wind, solar, and biomass systems.
Thermal Power Stations
Thermal power plants produce electricity from fossil fuels: coal, fuel oil, or gas. Spain has over 20 coal plants. The most important, producing over 1000MW, are in Bridge of Garcia Rodriguez Coruña, Compostilla in León, and Teruel. The main drawback is the environmental impact (emission of sulfur, nitrogen, and carbon oxides). Plants use techniques like fluidized bed coal combustion and coal gasification to reduce emissions and achieve greater efficiency. Fuel oil plants are being converted to CHP plants using natural gas as the main fuel.
Hydroelectric Plants
These plants use the potential energy of river water to convert it into electrical energy through turbine-generator groups. They differ by water harvesting and extraction methods. Current policies seek environmental preservation and energy efficiency, using small water flows with minimal environmental impact to supply remote areas.
Nuclear Power
Spain has nine nuclear power plants with a combined capacity of 7417 MW, supplying 37% of energy in 1998. The plants are: Jose Cabrera (Guadalajara, 1968), Sª Mª de Garoña (Burgos, 1971), ASCO II (Tarragona, 1985), Almaraz II (Cáceres, 1983), Asco I (Tarragona, 1983), Almaraz I (Cáceres, 1981), Cofrentes (Valencia, 1984), Thebarton II (Tarragona, 1897), and Trillo I (Guadalajara, 1988). The National Electric System Law halted the construction of new nuclear plants.
New Energy Production
In 1994, new energy production represented only 2.9% of total electricity production but is a developing sector. The Renewable Energy Program aims to increase primary energy production from these sources by 1.1 million toe per year, distributed as follows: Biomass and Municipal Solid Waste (72%), Small Hydro (19.3%), Solar Thermal (5.6%), Wind (3.1%), Geothermal (0.9%), and Photovoltaic (0.4%).
Electricity Consumption
The annual increase is expected at 3.4%, with estimates for the first decade of the century around 3%. In 1998, energy consumption increased by 6.8% over the previous year, and from January to August 1999, the increase was 6.4%.
Economic Activities
The most energy-intensive sector is business (43%), followed by domestic (24%), tertiary (23%), and agriculture and others (10%).
Geographical Distribution
The communities with the highest net per capita consumption are Asturias, Euskadi, Cantabria, and Navarra. Ceuta, Melilla, Extremadura, Canary Islands, and Andalusia have the lowest.
ENERGY CONSUMPTION IN EUROPE
: Between 1985 and 1996 energy consumption experienced a 14% increase, which was concentrated mainly in southern countries (Spain, Portugal, Greece) where economic growth has been higher than the European average. This increase is due to increased transport (+ 40%) and domestic services (11%), sectors that are gradually replacing diesel with natural gas. The main challenges facing the EU in the field of energy are:1. The increase in energy dependence, which has increased by 20% in recent years. 2. The need to ensure competitive prices through liberalization of markets for gas and electricity and the development of networks trans-European energy. 3. The need to reconcile the energy market with environmental objectives. 3.1 Energy production in the EU and the world primary energy production in the EU represents 8.4% of world production, This places it at a low level, however, the per capita energy consumption is in the environment of 3.8 toe per capita, higher value to most countries except the U.S., Japan and some OECD countries. 3.2 Energy supply: In the primary energy production is seen a boom inrecent years, largely due to oil production by more efficient and economical methods. Energy production in the EU in 1996, was distributed as follows: Nuclear power (29%) Natural gas (25%), Oil (20%), Coal (10%), lignite (7% ), Biomass (6%) and hydroelectricity (3%). If we compare the production and consumption of primary energy in each of the 15 EU member states, we note that most consumption is higher than its production, except the UK and the Netherlands. 3.3 Production of electricity EU: The production of this energy has been increasing, reaching 2409 TWh in 1996, with most of it is produced in thermal power stations (51%) and nuclear (35.2%). We highlight the increasing importance of nuclear energy and electricity production through systems that use natural gas as fuel.
3.4 Energy dependence of the EU: The EU does not meet their energy needs. The main imports are petroleum fuels and their derivatives (from OPEC countries and the Middle East) and natural gas (from Norway, Algeria and the former Soviet republics). The only country that produces more energy than it consumes UK, due to its reserves in the North Sea. 3.5 Production of renewable energy: The EU aims to boost the production of energy by renewable energy sources. In 1996 the contribution of renewable energy were 5.3%, but through the alternative program, set a target that by 2010, renewables proportions 12% of total energy demand. 4 THE ENERGY CONSUMPTION WORLD: The reasons for the evolution of energy demand is due to two factors: the income effect and substitution effect.4.1 Production and consumption of energy by geographical area: Most of the geographic areas are energy deficient, except OPED countries (oil producers and less industrialized). It defines the following areas: 1. North America (Canada, USA, Mexico): areas of high consumption. 2. South America: lower production and consumption, except Venezuela, part of OPEC. 3. Western Europe (Germany France, United Kingdom, Italy, Spain, Norway, Holland, etc..) deficit countries except UK and Norway. 4. Eastern Europe (Poland, GDR, etc.) losses. 5. USSR: the state of higher production the world. 4.2World energy resources: There are sufficient energy resources to maintain global demand for more than a century, but for each source, the picture is more optimistic: coal and uranium reserves are large, but the oil is much lower. Since oil reserves are concentrated in few countries, energy policies in importing countries are aimed at his replacement. 5 to save energy: Most of the energy resources are limited, therefore all actions must be aim to increase energy efficiency and environmental protection. 5.1 Less dependence on oil: By action to replace the latter and its derivatives by other fuels such as natural gas, nuclear and renewable energy consumption and save on those that it is impossible to replace. Reasons: oil prices affect the economy and oil derivatives are highly polluting.5.2 Improve the processes of energy transformation: Using techniques such as coal combustion in fluidized bed, coal gasification, combined cycle from gasified coal to produce electricity and heat, coal Hidrolicuefacción for easy transport and improving processes variety of petroleum fuels for more efficient and less polluting. 5.3 Changing consumption patterns: 5.3.1 Transport: You can contribute by using alternative energy such as biofuels (vegetable methyl ether) and natural gas (CNG), which reduce dependence on oil and the emission of pollutants (CO2, NOx, sulfur). The disadvantages that arise are mainly economic (high cost). 5.3.2Electricity: About half of the energy consumed in Western Europe goes to domestic and commercial buildings. The energy savings in this sector can be achieved by designing buildings with good insulation, efficient energy use in lighting control systems, energy efficient appliances for heating, air conditioning and refrigeration. In the industrial sector through advanced power control, installation of high efficiency lighting, etc.. 5.4 Natural gas. Using for domestic and industrial natural gas because of its high calorific value and their cost is gradually replacing the city gas and gases produced from the fractional distillation of petroleum (liquefied petroleum gas LPG), butane and propane . In the electricity sector are being replaced as power plants that use diesel fuel for CHP plants, where the main fuel is natural gas. In the public transport sector can be used natural gas focused.5.5 Rates night: For domestic and commercial use night rate implies lower per kWh during the night (called peak hours), back below 50% of those for the daytime. 6 ENERGY SAVING TECHNIQUES: 6.1 Cogeneration:
It is a technology that enables the production and use of combined heat and power: the steam generated in the boiler, besides being sent to the turbine generators to produce electricity, can be extracted at points on the turbine to provide heat for industrial processes or systems heating. These cogeneration systems make it possible to obtain higher energy yields and have less environmental impact, especially when the fuel used is natural gas. These systems have an overall efficiency in energy use over 80%. In recent years it has introduced the concept of trigeneration, which is based on the production of heat, electricity and cold.6.2 Heating: natural gas, heat
Petroleum fuels used in heating, can be replaced by natural gas, thus improving, the calorific value of fuel and reducing pollutant emissions.
The heat registers stored overnight, the energy required during the day. In this way you can take advantage of cheaper energy. 6.3 Lighting: energy-saving lamps. The replacement of the classic elements of lighting (incandescent and fluorescent) for higher performance lamps allows significant energy savings. The two most common are halogen and compact fluorescent lamps. The energy savings around 80% and its lifetime and efficiency are higher. 6.4 Home automation: This is a comprehensive control system that enables the user to control each and every one of the functions of its power grid and air-conditioning, electric current , appliances, awnings, lighting. The building operation schedule nightly rates or control of blinds and awnings depending on the climate, saves energy for air conditioning.6.5 Architectural solutions: One is using solar energy incident on the buildings, either through passive approaches (use of adequate insulation, double glazing, orientation) and active channel (solar energy capture to the greenhouse effect, or the walls and roofs of thermal inertia). 7 ALTERNATIVE ENERGY: The need to reduce consumption of non-renewable primary energy and environmental concern has led to technological development needed to make profitable inexhaustible energy resources such as: solar energy, wind , biomass, geothermal and tidal power. In 1998 renewable energy accounted for 6.3%, but with the Development Plan seeks to achieve by 2010 to 11.2%. To achieve this goal are offered bonuses in the electricity sector both fiscal and energy estructurales.Las most likely to use in our country are biomass, solar and wind.7.1 Biomass Energy and solid waste treatment: Obtained by the burning of agricultural waste, forestry, industrial, biodegradable products, etc., treated in thermal plants. Is used to produce heat in the industrial and domestic sector. The EU is the most used source, exceeding 55% of energy production energía.Otra is the derivative of “solid waste” MSW or household waste. The waste treatment is a separation of those materials that can be recycled, removal of organic matter for fertilizer and incinerating the remains utilization of heat to produce electricity. 7.2 Solar energy: There are two main groups: the thermal fotovoltaica.Los and solar thermal systems can be low, medium and high temperature. The low temperature (The largest CSP plant is in California (USA). In Spain there are 3 plants in Almeria.
Photovoltaic systems are an ideal solution for supplying electricity to isolated rural communities that do not require very high powers. 7.3 Wind power: It is an emerging sector in Spain, being the 5th largest producer of this energy. Spain has the largest wind farm Europa.Es the fastest growing energy source worldwide. Leader in the sector are Denmark, winning 8% of energy through this medium and with a forecast of 50% in 2030. To achieve higher productivity will be installed parks at sea where the wind speed is 20% higher than on land.