Energy conservation is the practice of decreasing the quantity of energy used. It may be achieved through efficient energy use, in which case energy use is decreased while achieving a similar outcome, or by reduced consumption of energy services.
Energy conservation can lead to:
- Increase of financial capital.
- Environmental value.
- National security.
- Personal security.
- Human comfort.
- Individuals and organizations that are direct consumers of energy who are dedicated to conserving energy in order to reduce energy costs and promote economic security.
- Industrial and commercial users who may want to increase efficiency and thus maximize profit.
No-Cost or Low-Cost:
- Lower your thermostat at night, and whenever the house is unoccupied, turn it off. Don’t heat unoccupied rooms (unless you have a heat pump). If you move your thermostat back 10 degrees Fahrenheit every night, you can reduce your heating bill by 10-20 percent.
- Lower the thermostat and dress warmer. As little as 1 to 3 degrees Fahrenheit makes a noteworthy difference in energy consumption.
- Lower the temperature on your electric water heater to 120 degress F. Turn it off when leaving for extended periods of time. Electric water heaters can be kept on.
- Rather than using a timer, set gas heaters manually.
- Set the refrigerator temperatures between 37 and 40 degrees F and clean the coils. Also, keep the refrigerator stocked; it takes more energy to cool an empty refrigerator.
- Consider replacing your older model refrigerator, especially if older than 10 years as older models can often use over 3 times the energy of newer models.
- Wash full loads of dishes and air dry.
- When washing clothes, use warm or cold water and rinse with cold. Air dry clothes, but not indoors as this creates unwanted mold and moisture problems.
- Shut off lights, computers and other electronic appliances when you’re not using them. Many computer monitors have a sleep mode setting which, when activated, greatly reduces energy consumption.
- Always use the bathroom or kitchen exhaust fans while showering or cooking and baking to avoid potential moisture problems.
- Use a microwave or toaster oven for smaller items.
- Install a low-flow showerhead. Showers use less hot water than baths; also consider taking shorter showers.
- Close your fireplace damper and seal the opening shut when not in use.
- During the heating season, open south-facing window coverings (e.g. drapes, blinds, etc.) during the day. Close all window coverings at night to keep the heat in.
- Install foam gaskets behind electric-outlet and switch-plate covers.
- If necessary, examine and adjust weather stripping, door sweeps, and thresholds.
Steps that cost more, but pay for themselves in two years or less:
- Install an automatic setback thermostat that adjusts room temperature according to your daily schedule. If you have a heat pump, be certain to use a special thermostat designed specifically for heat pumps.
- Install do-it-yourself weather stripping and caulking to seal air leaks. Seal all perimeter wall penetrations and ceiling and floor penetrations to stop all air movement between heated and unheated spaces.
- Install do-it-yourself storm windows that cost less than $1/sq.ft., such as flexible vinyl glazing.
- Use motion sensors or timers for outdoor lighting. You’ll still have security and save energy.
- Replace incandescent light bulbs in common areas (where lights are on most of the time) with compact fluorescent lamps (CFLs). They use about a quarter of the energy.
- Replace the halogen to richer floor lamp with a CFL model. They’re safer; use 70 percent less electricity and produce as much, if not more, light.
- Tune up the furnace annually.
- Replace furnace filters. The dirtier they are, the harder the fan furnace works. Clean filters are essential for heat pumps.
- Airflow is critical and can add years to the life of your heat pump.
- Add water heater tank and hot water pipe insulation especially if in an unheated space. Don’t cover the thermostat or, for natural gas models, the air inlets.
- Install a sheet metal fireplace cover, especially if the flue damper does not fit tightly.
Home energy improvements that pay for themselves in two to five years:
- Increase attic insulation to R-38 (the current requirement for new homes).
- Insulate floors over unheated spaces to R-19.
- Insulate and seal ducts in attics, crawl spaces, garages and other unheated areas - potentially big energy savings!
- Install do-it-yourself storm windows that cost less than $3/sq.ft/, such as rigid acrylic glazing.
- Perform low-cost fireplace modifications, such as flue top damper or inexpensive glass doors.
Home improvements that take more than five years to pay for themselves:
- When it is time to replace a home appliance, purchase an energy-efficient model. These appliances cost more initially, but you will save both money and energy over its entire life. An appliance that is cheaper to purchase will have higher operating costs, and savings you’ll accumulate from using an Energy Star appliance will be substantial.
- Energy Star® clothes washers save energy, water, and detergent.
- Energy Star ® windows only cost $0.50 / sq.ft. more than standard windows, and they save energy and increase comfort.
- Look for and purchase Energy Star ® labeled electronic goods, and lighting bulbs and fixtures.
- Add do-it-yourself insulated (quilted) window covers (minimum R-3 and costing less than $5/sq.ft.) or install blinds, drapes or other window coverings.
- Wall insulation should be added, especially when the wall cavity is made accessible during home remodeling. Depending on your siding type, consider blown-in insulation, applied from the exterior.
- Furnaces, heat pumps, air conditioning and water heaters all have high efficiency models available and should be considered when replacing these appliances.
- Invest in commercially installed storm windows or insulated glass.
- Replace conventional oil burner (oil furnace) with a more efficient flame-retention burner.
- Install a fireplace insert or wood stove in the fireplace.
- Install a solar water heater.
- Undertake regular energy audits.
- The maintenance in the plant should follow the "Zero Leak" philosophy, particularly in the areas of steam and utilities so that any loss of energy could be totally eliminated.
- Plug all oil leakage. Leakage of one drop of oil per second amounts to a loss of over 2,000 liters/year.
- Filter oil in stages. Impurities in oil affect combustion.
- Pre-heat the oil. For proper combustion, oil should be at the right viscosity at the burner tip. Provide heat capacity.
- Incomplete combustion leads to wastage of fuel. Observe the color of smoke emitted from the chimney. Black smoke indicates improper combustion and fuel wastage. White smoke indicates excess air and hence, loss of heat. Hazy brown smoke indicates proper combustion.
- Use of low air pressure "film burners" helps save oil up to 15 per cent in furnaces.
- All possible attention should be paid to control excess air by monitoring oxygen level in flue gas and also by visual inspection of flame color.
- Use only treated water in boilers. A scale formation of 1mm thickness on the waterside would increase fuel consumption by five per cent to eight per cent.
- Remove soot deposits when flue gas temperature rises 40°C above the normal temperature. A coating of 3mm thick soot on the heat transfer surface can cause an increase in fuel consumption of as much as 2.5 per cent.
- Recover heat from steam condensate. For every 6°C rise in boiler feed water temperature through condensate return, there is a one per cent saving in fuel.
- Soot blowers can always be maintained in perfect working conditions so that their regular and periodic use does not suffer.
- Improve boiler efficiency. Boilers should be monitored for flue gas losses, radiation losses, incomplete combustion, blow down losses, excess air, etc.
- Proper control can decrease consumption up to 20 per cent.
- Stop steam leakage. Steam leakage from a 3mm-diameter hole on a pipeline carrying steam at 7 kg/cm² wastes 32 kilolitres of fuel oil per year.
- A poorly maintained injection pump increases fuel consumption.
- A faulty nozzle increases fuel consumption.
- Blocked filters increase fuel consumption.
- A continuously-running DG set can generate 0.5 ton/hour of steam at 10 bars to 12 bars from the residual heat of the engine exhaust per MW of the generator capacity.
- Measure fuel consumption per kWh of electricity generated regularly. Take corrective action in case this shows a rising trend.
- Compressed air is very energy intensive. Only five per cent of electrical energy is converted to useful energy. Use of compressed air for cleaning is rarely justified.
- Increase in inlet air temperature by 3°C increases power consumption by one per cent. Ensure low temperature of inlet air.
- Reduction in discharge pressure by 10 per cent saves energy consumption up to five per cent. It should be examined whether air at lower pressure can be used in the process.
- A leakage from a ½" diameter hole from a compressed air line works at a pressure of 7 kg/cm.
- Air output of compressors per unit of electricity input must be measured at regular intervals. Efficiency of compressors tends to deteriorate with time.
- Select a pump of the right capacity in accordance with the irrigation requirement. Improper selection of a pump can lead to a large waste of energy. A pump with 85 per cent efficiency at rated flow may have only 65 per cent efficiency at half the flow.
- Match the motor with the appropriate-sized pump.
- Using throttling valves instead of variable speed drives to change flow of fluids is a wasteful practice. Throttling can cause wastage of power to the tune of 50 per cent to 60 per cent.
- It is advisable to use a number of pumps in series and parallel to cope with variations in operating conditions by switching on or off pumps rather than running one large pump with partial load.
- Void valves in the pipe line throttle wastes energy. A positive displacement pump with variable speed drive is recommended.
- Proper installation of the pump system, including shaft alignment, coupling of motor and pump is a must. Drive transmission between pumps and motors is very important. Loose belts can cause energy loss up to 15 per cent to 20 per cent.
- Use efficient transmission system. Maintain right tension and alignment of transmission belts.
- Use of modern synthetic flat belts in place of conventional V belts can save five per cent to 10 per cent of energy.
- Properly organized maintenance is very important. Efficiency of worn-out pumps can drop by 10 per cent to 15 per cent, unless maintained properly.
- Use low friction rigid PVC pipes and foot valves.
- Avoid use of unnecessary bends and throttle valves.
- Use bends in place of elbows.
- The suction depth of six meters is recommended as optimum for centrifugal pumps. The delivery line should be kept at the minimum required height in Keeping with requirements.
- Periodically check pump systems and carry out corrective measures such as lubrication, alignment, tuning of engines and replacement of worn-out parts.
- Over-irrigation can harm the crops and waste vital water resource. Irrigate according to established norms for different crops.
- Use drip irrigation for specific crops like vegetables, fruits, tobacco, etc. Drip systems can conserve up to 80 per cent water and reduce energy pumping requirements.
- The motors should be energy efficient.
- Convert delta to star connection for lightly-loaded motors.
- Install soft start–cum-energy saver for lightly-loaded motors.
- In case of centrifugal blower pump, install variable voltage frequency drives for speed control of motors.
- Install multi-speed motor.
- Optimize operating voltage level of motor for lightly loaded motors
- Replace eddy current controls with variable frequency drives for varying speed driven equipment.
- Provide interlock for electric motor to avoid idle running.
- Replace motor generating sets with thyristor drives.
- Avoid frequent rewinding of motors. Greater the number of rewind, lesser the efficiency.
- Carry out preventive maintenance and condition monitoring schedule regularly.
Advantages of Energy Efficient Motors:
- Reduced operating costs.
- Less heat losses.
- Extended winding lifespan.
- Extended lubricating grease service life.
- Lower noise levels than other motors.
- Reduced energy costs. The higher purchase price investment pays off.
- Reduce emission of CO2 and NOx greenhouse gasses from power stations for positive environmental effect.
Refrigeration and air conditioning:
- Close doors and windows while running the air conditioning. Don't use a whole-house fan or window fan while the air conditioner is on, but do use a ceiling fan .
- Use of double doors, automatic door closures, air curtains, double glazed windows, polyester sun films etc. reduces heat ingress and air-conditioning load of buildings.
- Maintain condensers for proper heat exchange. A 5°C decrease in evaporator temperature increases specific power consumption by 15 per cent.
- Utilization of air conditioned/refrigerated space should be examined and efforts made to reduce cooling load as far as possible.
- Utilize wasted heat of excess steam or flue gases to change over from gas compression systems to absorption chilling systems and save energy costs in the range of 50 per cent to 70 per cent.
- The compressor of the central air conditioner should be located in a cool, shaded place outside.
- Specific power consumption of compressors should be measured at regular Intervals. The most efficient compressors should be used for continuous duty, while other are kept on a standby.
- The air conditioning unit must be inspected, cleaned and tuned by a professional every two to three years to keep it going longer and to use less electricity. If the refrigerant needs to be recharged, make sure it is done correctly. If it is overcharged, it would reduce operating efficiency and could damage the unit. If it Is undercharged, it would also use energy less efficiently.
- The duct system should be properly sealed. This could save 10 per cent to 15 per cent of the electricity into air conditioner.