Energy Efficiency

Energy Efficiency

Energy efficiency, means using less energy to provide the same level of energy. It is therefore one method to reduce human greenhouse gas emissions.  For example if a house is insulated, less energy is used in heating and cooling to achieve a satisfactory temperature. Another example is installing fluorescent lights or skylights, instead of incandescent lights, to attain the same level of illumination.

Efficient energy use is achieved primarily by means of a more efficient technology or process. Energy efficient buildings, industrial processes and transportation could reduce the world’s energy needs in 2050 by one third, and help controlling global emissions of greenhouse gases.  Making homes, vehicles, and businesses more energy efficient is seen as a largely untapped solution to addressing global warming, energy security, and fossil fuel depletion. The 1973 oil crisis, where oil prices were very high, focussed attention on energy efficiency.

Energy-efficient appliances

Refrigerators, freezers, ovens, stoves, dishwashers, and clothes washers and dryers, can be designed to reduce the amount of electricity they use.  Modern energy efficient refrigerators, for example, use 40 percent less energy than those of 2001.  Power management systems also reduce energy usage by idle appliances by turning them off or putting them into a ‘low-energy mode’ after a certain time. Many countries identify energy-efficient appliances using an Energy Star or energy efficiency labels.

Energy-efficient building design

The location and surroundings of buildings can help in regulating internal temperature and illumination.  For example, trees, landscaping, and hills can provide shade and block wind. In cooler climates, designing buildings with an east-west orientation to increase the number of south-facing windows minimizes energy use, by maximizing passive solar heating.  Energy-efficient, well located windows, well-sealed doors, and thermal insulation of walls, basement slabs, and foundations can reduce heat loss by 25 to 50 percent.

Energy Management

When it comes to energy saving, energy management is the process of monitoring, controlling, and conserving energy in a building or organization. Typically this involves the following steps:

  • Metering your energy consumption and collecting the data.
  • Finding opportunities to save energy, and estimating how much energy each opportunity could save. You would typically analyze your meter data to find and quantify routine energy waste, and you might also investigate the energy savings that you could make by replacing equipment (e.g. lighting) or by upgrading your building’s insulation.
  • Taking action to target the opportunities to save energy (i.e. tackling the routine waste and replacing or upgrading the inefficient equipment). Typically you’d start with the best opportunities first.
  • Tracking your progress by analyzing your meter data to see how well your energy-saving efforts have worked.

Energy management is the key to saving energy in your organization. Much of the importance of energy saving stems from the global need to save energy – this global need affects energy prices, emissions targets, and legislation, all of which lead to several compelling reasons why you should save energy at your organization specifically.

Organizational integration in energy

Many organizations use a siloed approach toward energy management. One department manages contracts. Another may work toward reducing usage, while another is tasked with accomplishing sustainability goals. There is no cohesive strategy for buying, managing and monitoring energy.  That’s what integrated energy management is all about—having a unified view of your organization’s energy and a plan for using it as efficiently as possible. It’s using a holistic approach to address all aspects of energy usage, from purchasing electricity to measuring the return on investment (ROI) of renewable energy projects.

Integrated energy management is more than a buzzword. It’s a long-term approach that requires buy-in from key stakeholders, thoughtful planning and tapping into the expertise of professionals who have the ability to put your plans into action.

Energy Management in Operational Functions

Energy is an integral part of today‟s modern life. It has become the blood of our day to day life. But it is not free. It comes at a monetary price but more than that it comes at environment cost too. It is very difficult to think about our modern life without energy. But the generation of energy requires natural resources which are depleting day by day. On the other side, use of energy is increasing exponentially. In developing nation like India, about 49% of total commercial energy is consumed in industries and utilities like Compressed Air, Air Conditioning, Steam, Hot water, Electrical systems, fuel, water system consumes substantial part of total energy in these industries.

The judicious and effective use of energy to maximize profits (that is, minimize costs) and enhance competitive positions is energy management. Therefore, any management activity that affects the use of energy falls under this definition. The primary objective of energy management is to maximize profit and minimize costs by optimizing energy procurement and utilization, throughout the organization to minimize energy costs without affecting production and quality and to minimize environmental effects.

There are many motivational forces for energy management presently acting on the industrial sector:


Although energy cost may constitute a relatively small part of total operating cost, for many industries, it is one of the most manageable resources among labor and material. Reductions in energy consumption and thereby reducing energy cost are very vital for any industry to remain competitive.



Short Falls in power supplies

Due to limitations in power supply infrastructures, many industries face power supply problems in terms of reliability and quality of the power supply and increasing energy demand and industrialization have led to predictions of a serious supply shortfall.

Environmental Management Systems

In certain parts of the world, especially in Europe, ISO 14001 standard on environmental management is increasingly becoming a requirement for trade. Energy management is an important component of environmental management and waste reduction strategies, and features significantly in ISO14001.

Global Climate Change

The global climate is changing because of human activity, and that one of the major causes of climate change is the emission of Greenhouse Gases (GHG), principally CO2, into the atmosphere from the combustion of fossil fuels. Since fossil fuels, directly or indirectly, are important energy sources to industry, there is international pressure to reduce GHG emissions by reducing energy consumption.

Energy Purchase

A Power Purchase Agreement (PPA) secures the payment stream for a Build-Own Transfer (BOT) or concession project for an independent power plant (IPP). It is between the purchaser “offtaker” (often a state-owned electricity utility) and a privately owned power producer. The PPA outlined here is not appropriate for electricity sold on the world spot markets . This summary is focused on a base load thermal plant (the issues would differ slightly for mid-range or peaking thermal or hydro plants).

  • Where a government agency enters into an arrangement for a private power company to establish a power plant and sell on the power to the government agency, the public agency typically enters into a PPA.
  • The PPA usually takes the place of a BOT or concession agreement: in addition to obligations relating to the sale and purchase of the power generated, the PPA also sets out the required design and outputs and operation and maintenance specifications for the power plant.
  • Sale of capacity and energy – the power producer agrees to make available to the Purchaser the contracted capacity of energy and deliver the energy in accordance with the PPA.
  • Charges for Available Capacity and Electrical Output – the charging mechanism in the PPA is generally a pass through arrangement: the price charged for the power will consist of a charge (availability charge) to cover the project company’s fixed costs (including a return on equity for the project company) plus a variable charge to cover the project company’s variable costs. The availability charge relates to the availability of the power plant and the variable charge is calculated according to the quantity of power supplied. The purchaser will want a guaranteed long-term output from the project and so the availability charge is typically the minimum that it will be paid, provided that the plant can be shown to make sure power available.

Energy production planning and control

Over the last decades, the production planning process of factories had to take more and more additional production factors into consideration. In the past, production factors like work force, machine capacity and material were focused  on meeting the main production goals, namely time, cost and quality . Due to the changes in the energy market, the resource energy has developed steadily from an unlimited resource to an indispensable production factor.

The production planning and control of a factory is usually supported by computer-based systems. These systems ensure an effective and efficient production process by the use of their planning tasks with a strong focus on dates, capacities and quantities. In addition to the planning tasks, the systems are responsible for data storage, handling and communication throughout the computer-based systems and subsystems of the factory’s operations . Within the field of manufacturing, the following computer-based systems can be distinguished.

  • Supply Chain Management Systems (SCM)
  • Enterprise Resource Planning Systems (ERP)
  • Manufacturing Execution Systems (MES)
  • Production Data Acquisition (PDA)


Energy maintenance

As engineering and maintenance managers are aware, all building systems and components need some level of maintenance, and renewable-energy systems are no exception to this rule. The specific maintenance requirements vary based on the type of system and components installed.

For all renewable-energy systems, it is proper maintenance practice to inspect the integrity of mechanical and electrical connections at least once each year. Corroded or loose connections can result in decreased performance, and in extreme cases, they can create safety hazards.

Solar hot-water systems require periodic inspection of the panels for leaks, damage, and even build-up of dirt on panel surfaces. If the systems use a water-glycol mixture, technicians should test the system periodically for proper concentrations of glycol. They should inspect and test drain-down systems before the onset of cold weather to ensure the panels drain fully.

Solar electric systems also require periodic inspection of the panels for physical damage, dirt build-up, and proper tightness of the electrical connections. Technicians also should make certain vegetation growing near the installation does not block sunlight to the panels. Shadows that fall on even part of one panel can cause a significant reduction in the system’s total output. Solar electric systems also require that technicians periodically test the output from system inverters.

Wind-turbine systems require similar testing and inspection of electrical connections and inverters.Technicians also should inspect all of the system’s moving parts, including turbine blades and bearings, for damage at least once each year, according to manufacturer recommendations.

Geothermal systems have relatively low maintenance requirements, compared with other renewable-energy systems. Most geothermal systems use a water-source heat pump, in which the system circulates water through a loop buried in the ground.  The maintenance requirements parallel those for other heat-pump systems, with the exception of the buried loop. As long as workers install the system properly and nothing disturbs the ground in the area of the underground piping, no additional maintenance requirements should exist.

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