The idea of a sustainable society is centered on maximizing human well-being, preserving environmental and corporate assets, and developing measurement standards that clearly define personal, social, and environmental health. Rather than viewing society as a market and individuals as consumers, a sustainable society prioritizes the well-being of its citizens and the environment, both in the present and future.
Thermodynamics is a discipline concerned with the relationship between heat, work, temperature, and energy. In practical terms, it deals with the transfer of energy from one place to another and from one form to another. We can see the principles of thermodynamics at work in many everyday devices, such as computers, televisions, water heaters, irons, pots, gas and electric ovens or heaters, and air conditioners.
Exergy, also known as the “quality of energy,” refers to the potential energy contained in a thermodynamic system relative to a reference state. It is a measure of the usefulness of a flow of energy. Exergy can be fully utilized in the form of electricity and fuels, in which case its exergy value is equal to its energy value. However, in the case of internal energy and thermal energy, the work potential is lower than the amount of energy.
Energy use in buildings is often centered on heating and cooling systems. Improving these systems can reduce waste energy and increase efficiency. In addition to minimizing exergy losses, it is also desirable to minimize exergy inputs by using low-quality energy sources for low-quality energy needs. This can be achieved by matching the energy needs and the quality levels of the energy source.
Buildings are major consumers of energy. Energy is needed for both heating and hot water in buildings. One approach to reducing energy needs in buildings is to increase insulation and reduce air leakage in the building envelope. It is also important to make optimal use of the building’s structure and to take advantage of renewable energy sources.
Here are a few examples of ways to increase energy efficiency in buildings for a sustainable society:
Insulation: One of the most effective ways to reduce energy use in buildings is to increase insulation in the building envelope (walls, floors, and roofs). This helps to keep heat in during the winter and out during the summer, reducing the need for heating and cooling.
Lighting: Replacing traditional incandescent light bulbs with energy-efficient LED bulbs can significantly reduce energy use.
Windows: Installing energy-efficient windows with low-emissivity (low-E) coatings can help to reduce heat loss in the winter and heat gain in the summer, improving the energy efficiency of a building.
Heating and cooling systems: Upgrading to high-efficiency heating and cooling systems can significantly reduce energy use. For example, a high-efficiency furnace or air conditioner may use 30% less energy than a standard model.
Renewable energy sources: Incorporating renewable energy sources, such as solar panels or geothermal heat pumps, into a building’s energy system can help to reduce reliance on fossil fuels and improve energy efficiency.
Combined heat and power (CHP) systems generate both electricity and heat, and can also feed useful heat into a district heating network. CHP systems are based on the principle of a combined heat and power plant. The main purpose of CHP plants is to produce heat and electricity simultaneously. The heat produced by CHP systems can be used in industrial facilities as process steam, or in homes, offices, campuses, shopping malls, and mass housing as heating and hot water. CHP systems have the potential to achieve a total yield rate of over 90%.
Here are a few examples of CHP systems:
Industrial CHP: CHP systems are used in many industrial facilities, including factories, refineries, and power plants, to generate electricity and process steam.
District heating: CHP plants generate electricity and heat in district heating systems, which are then distributed to multiple buildings via a network of pipes.
Commercial CHP: CHP systems can also be used to generate electricity and provide space heating and hot water in commercial buildings such as office buildings, shopping malls, and hospitals.
Residential CHP: CHP systems are also being used by some homeowners to generate electricity and heat for their homes. Natural gas, biomass, and other fuels can be used to power these systems.
In summary, the exergy approach to energy use in buildings involves matching the quality levels of the energy supplied to the quality levels of the energy demanded and using low-quality energy sources for low-quality energy needs. CHP systems, which generate both electricity and heat, offer a highly efficient method of meeting energy needs in a sustainable way.
We can reduce our reliance on non-renewable energy sources by using energy more efficiently. This can help to reduce greenhouse gas emissions, air pollution, and other environmental consequences of energy production and use. Furthermore, increasing energy efficiency can help to lower energy costs for individuals, businesses, and governments, which can help to improve economic sustainability.
Overall, energy efficiency is an important part of creating a more sustainable society, as it helps to reduce our environmental impact and improve our ability to meet the needs of the present and future.