Instant Water heaters provide hot water when it is needed and one does not have to wait for the storage tank to fill up. Water is heated instantly when the cold water enters the unit, which can provide hot water at a rate of 7.6 – 15.2 liters per minute. Water is heated through an electric unit and the electricity needed for instant electric water heaters is very high. Wattage of water heater makes the water heat faster or slower i.e. a water heater of 4.5 kW will heat faster than a water heater of 2 kW.

Storage Water heaters store water in a big container and heat it up. Effective thermal insulation for storage water heater is very important as it can have standby heat losses (BEE 5 star rated water heaters have lower standby heat losses in comparison to the others). This kind of water heater is ideal for situations where there is lot of use of hot water (for multiple activities or multiple people). The ideal size of water heater should be close to the volume of hot water required at one go.

Solar Water heaters are the most efficient and economical way of water heating. They include a well-insulated storage tank and solar collectors. There are two types of solar water heating systems: active, which have controls and pumps circulating water through the collectors and into the home, and passive, which don’t. The only drawback is that a backup system is required for them for cloudy days or in case of increased demand.

How much hot water do I need for:

• Taking a shower: 25 liters per shower
• Washing the clothes of one person: 10 liters per wash
• For washing dishes after one meal: 5 liters per meal

To save energy:

• Switch on the water heater before use and switch it off immediately after.
• Use smaller sized water heaters because electricity consumed is dependent on the amount of water heated.
• The more hot water you use, the more electricity it will consume.
• Branded water heaters use better quality material for making the water heater.

Water heater waste energy when:

• Unused water is left in the water heater.
• Water heater is left switched on for a long period of time.

LINKS:

Bijli Bachao

Bureau of Energy Efficiency (BEE)

Two types of home refrigerators are available in the market:

Direct cool refrigerators are the most basic types where cooling within the fridge compartment is done without any fanning. There is no frozen storage compartment and the cooling is rather done by a natural convection within the refrigerator where one part may become cooler than another area inside the compartment. These refrigerators are more energy efficient but require manual defrosting periodically. This segment includes under it only a few single-door refrigerators.

Almost all modern refrigerators are frost free refrigerators using electric fans to circulate cool air inside the chambers along with door cooling technology. Every six hour or so, a timer turns on a heating coil wrapped around the freezer coils and melts the ice around it. When all the ice is removed, the temperature sensor senses the temperature rising above 0ºC and turns off the heating coil. The end result also plays a part in ensuring long work life to refrigerator components. These models do not require you to manually defrost them from time to time. Moreover, frost free refrigerators are efficient at keeping a consistent temperature throughout the fridge cavity.

Life span and cost

A typical refrigerator has a lifespan of 15 to 20 years and the cost of running it over such time period is several times the initial purchase price. Therefore it is important to buy the most efficient model available. A BEE 5-star rated refrigerator that costs more initially will have lower operation costs because of better construction and insulation, and will pay for itself in less than four years compared to a 2-star refrigerator. Models with top bottom mounted freezers use 12 per cent less energy than side-by-side designs.

Before buying the refrigerator

Before buying a refrigerator, it is important to consider its energy efficiency aspects apart from price, warranty, after-sales service, etc. In this context, while selecting a refrigerator, do refer to the BEE Star Rated Label affixed on the refrigerator and also refer to the Star Rating analysis promoted by BEE from time to time through its web site (www.bee-india.nic.in).

Choosing the right size

Make sure you are choosing a refrigerator that is approximately sized for your storing and cooling needs. If your fridge is too small, you may be overworking it. If it is too large, you are paying higher initial cost, and potentially wasting energy and home space. Always ascertain the storage volume of the refrigerator because this is the actual space available to you for storing food items.

Tips

• While placing the refrigerator in home, ensure that it is at least 100 mm (4 inches away) from the walls to facilitate effective working. If the heat does not escape, the refrigerator’s cooling system will work harder and use more energy.
• Don’t keep your refrigerator or freezer too cold. Recommended temperatures are 35-38 °F (1 -3 °C) for the fresh food compartment and 0° F (-18 °C) for separate freezers for long-term storage. You can check the refrigerator temperature by placing an appliance thermometer in a glass of water in the center of the refrigerator. Read it after 24 hours. Check the freezer
• The refrigerator unit should also be leveled appropriately to ensure that its door closes easily and tightly after its use to minimize unwanted warm air infiltration in the cooling space.
• Allow hot and warm foods to sufficiently cool down before putting them in refrigerator. It is also advisable to put them in sealed (air tight) containers. Uncovered foods release moisture and make the compressor work harder.
• When dust builds up on refrigerator’s condenser coils, the compressor works harder and uses more electricity. Therefore clean the coils regularly

Top Models

There are multiple types and brands of refrigerators or fridges available in the market today and Bijli Bachao have decided to put up a list of “Top Ten refrigerators in India” by electricity consumption and size. To consult the list, simply click on Top Ten.

Useful Links:

• Bureau of Energy Efficiency
• Centre for Science and Environment, India
• Bijli Bachao

LED emits light when voltage passes through a semiconductor material (a light emitting diode) embedded in a plastic capsule. Assembled into a light bulb, LEDs come to full brightness without need for a warm-up time. Their lifespan and electrical efficiency is several times better than incandescent lamps and significantly better than most fluorescent lamps. On the other hand LEDs emit light in a very narrow band of wavelengths and their directional characteristics affect the design of lamps. Although LEDs are currently more expensive on an initial capital cost basis, when considering the total cost during its long useful life, they are much less expensive to run.

A compact fluorescent light (CFL) uses a tube and a compact electronic ballast in the base of the lamp. The tube is curved or folded to fit into the space of an incandescent bulb and can produce warm tones of light. CFLs use 20-40% less electricity and last 8 to 15 times longer than standard incandescent lamps. CFLs are more expensive to purchase but in the long run they represent a much better economical option. However when you get rid of an old CFL it will likely break if buried in landfills and release toxic mercury vapor, which can contaminate water and enter the atmosphere. Unless Auroville can ensure a take-back system for such harmful waste, we cannot recommend changing ordinary bulbs with CFLs

An incandescent bulb produces light when an electric current passing through a wire filament heats it to a high temperature and makes it glow. Incandescent bulbs vary from 15 to 150 watts and produce usually a soft yellow-white light emitted in all directions. Incandescent bulbs are much less efficient than most other types of electric lighting. They convert less than 5% of the energy they use into visible light (with the remaining energy being converted into heat).

A halogen lamp is an incandescent lamp that has a small amount of a halogen such as iodine or bromine added. They produce a bright, white light of a higher luminous efficacy than incandescent bulbs. Halogen lamp can be operated at a higher temperature so they require more caution when handling. The small size and intensity of halogen lamps make them great for task lightning (e.g. compact optical systems for projectors and illumination).

For a night lamp many are using a “Zero watt” bulb, which is called so due to the inability of the older meters to accurately measure their power consumption. But now the advanced meters ensured that even a fraction of a power consumed by any appliance does not go unnoticed. Therefore Zero watt bulbs do consume at least 5 W of power and since some people switch them on 24h a day, it means that such small bulb consumes 45 kWh per year. If you need a night lamp, there are several LED alternatives available these days that consume just 1 W and produce almost the same amount of light. And LEDs being long lasting, it will keep it going for years.

When shall I replace existing light bulbs?

Considering the sum of all the energy required to produce a light bulb, it should only be replaced when it has completed its life, and not during its life cycle. Wastage of embodied energy is as bad as wastage through inefficient energy usage.

Energy efficient light bulbs

For decades nearly everyone filled their house with incandescent bulbs and brightness was measured in watts. Its measurements was featured on the front of each light bulb package, even though watts are the indication of how much power a bulb consumes – not the amount of light it generates. With the introduction of energy-saving bulbs using a lot less power to produce the same amount of light, reliance on watt measurements alone make it difficult for people to compare traditional incandescent bulbs to more efficient bulbs.

Nowadays the efficiency of a light bulb is defined in lumens and watts and new efficiency standards require lightbulbs to consume less electricity (watts) for the amount of light produced (lumens).

What is Lumen?

Lumens is a measure of brightness indicating how much light you are getting from a bulb. More lumens means that it is a brighter light; if you want something dimmer, go for less lumens. You can use the following chart to see equivalent watt and lumen (Brightness) for different types of bulbs.

As shown in the above chart, to have 700 lumens of light, you can either chose a:

• 10 watts LED bulb, which is more energy efficient and has a life time of 25,000 hours.
• 12 watts CFL lasting 12,000 hours.
• 42 watts Halogen having a life time of 2,500 hours.
• 60 watts incandescent bulb with a life time of 1,000 hours.

Lightbulb efficiency is also measured in terms of lumens per watt—the amount of light produced for each watt of electricity consumed:

So whenever buying new bulbs, think lumens – not watts.

Useful Links:

Bijli Bachao

Bureau of Energy Efficiency

Before Cleanup

• Have people leave the room.
• Air out the room for 5-10 minutes by opening a window or door to the outdoor environment.
• Shut off the conditioning system, if you have one.
• Collect materials needed to clean up broken bulb:
  • stiff paper or cardboard;
  • sticky tape;
  • damp paper towels or disposable wet wipes (for hard surfaces); and
  • a glass jar with a metal lid or a sealable plastic bag.

During Cleanup

• DO NOT VACUUM.  Vacuuming is not recommended unless broken glass remains after all other cleanup steps have been taken.  Vacuuming could spread mercury-containing powder or mercury vapor.
• Be thorough in collecting broken glass and visible powder.  Scoop up glass fragments and powder using stiff paper or cardboard.  Use sticky tape, such as duct tape, to pick up any remaining small glass fragments and powder. Place the used tape in the glass jar or plastic bag.
• Place cleanup materials in a sealable container.

After Cleanup

• Promptly place all bulb debris and cleanup materials, including vacuum cleaner bags, outdoors in a protected area until materials can be disposed of.  Avoid leaving any bulb fragments or cleanup materials indoors.
• Continue to air out the room where the bulb was broken and leave the air conditioning system shut off for several hours.

Source: US Environmental Protection Agency

Useful Link: Recycle the Bulb

Things to consider when choosing the size of the ceiling fan
Choosing the right size for a ceiling fan will optimize its performance and efficiency. A large fan in small room or a small fan in a large room will be a total misfit. Therefore the following points should be considered if you want a freshening airflow.

1. The size of the room: the proper ceiling fan size is determined by the room it will be placed in. For best results, the fan should be as close to the center of the room as possible. To get best results it should be at least 8-9 feet (245-275 cm) from the ground level and 1 feet (30 cm) below the ceiling. In a small size room the blade edge should be at least 18 inches (45 cm) away from the wall.
2. The number of blades: as the number of blades goes up, a fan tends to be quieter and circulate less air. Additional blades increase the drag on the ceiling fan’s motor and will slow it down. This is one of the reasons why industrial fans (like wind turbines) usually have only two or three blades: they can go faster, move more air and noise isn’t so much of a concern for them.
3. The size of the blades: when the fan is switched on, the diameter of the visible circle made by the blades sweep is the full size of the blade span.

Source: Lumens.com

Energy Efficient Models
Most people focus on lighting for reducing their electricity consumption even though fans consume a lot more than lights. To give you a perspective, a regular (non BEE1 star rated) ceiling fan consumes 75 Watts as compared to a regular (most inefficient) tubelight that consumes 55 Watts. Moreover a ceiling fan is used during the day as well as night whereas a light is used only during the night. In totality ceiling fans consumes more than twice or thrice the amount of electricity as compare to lights.

This is the reason why it is important to become aware of the power consumption of ceiling fans while buying them. To help you making electricity consumption as one of the deciding factor, Bijli Bachao2 has put up a list of Top Ceiling Fans in India by electricity consumption and performance.

Their ranking, for the standard size 48 inches (1200 mm) sweep fans, is based on data obtained from BEE on air delivery of a ceiling fan (i.e. volume of air and the rate at which it moves) and power consumption (i.e. amount of energy in Watts used to run a fan at high speed). The actual calculation of air delivery / power consumption for various models of ceiling fans ascertains their “Service Value”, which is being used for ranking purpose. The one with the maximum Service Value is given the highest ranking while multiple models with the same value are given the same rank.

Airflow Efficiency: Top Five Ranking of 1200 mm Sweep Fans

Source: Bijli Bachao

As a comparison, Bijli Bachao used an energy meter to measure the power consumption of various fans. You will find below the results of their testing, to which we added a column showing the annual consumption assuming that the fan is working daily for 18 hours.

SuperFan:

BEE 5-Star Rated Fan (a fan similar to the regular ones but with a slightly efficient motor):

Regular Ceiling Fan (2-3 year old in fair condition):

Regular Ceiling Fan (8 year old in bad condition):

¹ BEE or Bureau of Energy Efficiency in India

Useful Links:

Bilji Ba chao

Bureau of Energy Efficiency

1. Which capacity should my AC have?
   
   In most cases 1 TR (ton) capacity will do. In case of larger rooms (>25m2) please consult AVES.
2. Should I chose a window or split type of fixture?
   Considering energy efficiency and convenience factors (noise, etc.), we recommend only split type ACs.
3. What type of compressor should I select: inverter or non-inverter?
   Inverter technology is the most energy efficient at the moment. These ACs have a variable speed compressor. Instead of switching on and off as happens with the conventional compressors, the speed of the compressor of an inverter-type AC varies with the cooling energy required. The image below demonstrates the difference between inverter and non-inverter type ACs.

However one should consider that:

• Inverter type ACs are generally Rs. 10,000+ more expensive
• Manufacturers may not provide warranty on the inverter (although it is said that Inverter type system is less prone to breakdowns because it does not switch on and off continuously).

An alternative option would be a non-inverter type with a BEE (Bureau of Energy Efficiency) rating. In case you consider purchasing non-inverter AC, we would recommend to only consider models having a 5-Star Energy Efficiency label.
Note: Inverter ACs do not have start ratings yet, but they are 20 to 30% more efficient than non-inverter types.

1. Which models can give me good support services?
   It is important to count on the quality and the accessibility of support services. You will find below a list of manufacturers having Pondy-based service support: LG, Samsung, Carrier, Hitachi
   Although Daikin is offering models that are appreciated by many Aurovilians, as of now they still have unreliable support in our region.

Below are a few links to ease your search of a right model:

• http://goo.gl/VsmL3D
• http://goo.gl/qxOgG
• http://goo.gl/WtRPHT
• Bilji Bachao
• Bureau of Energy Efficiency