Why this ELECTRICITY?

Consume lavishly, enjoy until bill will receive OR consume it effectively, enjoy both bill and life comfort.

By Eng. Navodana Kankanamge

Although electricity tariff has been modified recently; still generation cost of electricity is higher than the selling price in Sri Lanka. Only way to reduce the electricity bill is improving the efficiency and the effectiveness of electricity usage. It is obvious that Electrical Engineers in the country may lead for this discussion. Following facts may helpful to somebody who heartily interest to reduce the electricity consumption without lose life comfortable.

Refrigerators 

Refrigerators play an essential role in modern life. They provide steady cooling and among other things allow us to easily preserve goods. It is estimated that almost 50% of the domestic energy consumption is responsible by the refrigerator. There are 4 million domestic consumers in the country and it is estimated more than 60% among them are using a refrigerator. Energy consumption of a refrigerator affect following factors.
When choosing a location with the needed clearances for placing the refrigerator, you need to consider the temperatures in the area. If the temperatures are too warm, the refrigerator will run more often and waste more energy. Air circulation helps keep the temperature around the refrigerator. Don’t place the refrigerator right up against the wall; the warm air from the refrigerator compressor has nowhere to escape. Normally refrigerator maintains an interior temperature at 400 F in the refrigerator and 00 F in the freezer for safe food storage. If the distance is not adequate from the wall, the warm air is trapped around the unit, which will make it run more often while trying to keep the internal temperature correct. The best possible practice is placing a louver type tall window to the wall, where refrigerator going to be placed to allow to circulation of natural ventilation to cool down it.
Compressor running duration increases with number and duration of door openings since the cold air inside comes out from the bottom of it and replaces with hot air from outside. If you difficult to control door openings, plastic air curtain can be used, which can trap cold air successfully since door opens. It is very cheaper and simple improvement to reduce the energy consumption.
Foods in freezer put about half an hour inside to refrigerator section before use. It will help to reduce compressor load. If it is leaking cool air from the door, magnetic rubber beading needs to clean or replace. When foods left uncovered inside the refrigerator, it will leach this moisture into the air and the compressor of refrigerator will have to work twice as hard to remove it. Using empty bottles, containers, or even store bought water jugs can help keep space full and it helps keep things cold.
Sources/References: http://en.wikipedia.org/wiki/Refrigerator, http://www.treehugger.com/kitchen-design/would-a-fridge-curtain-save-electricity-or-should-you-just-unplug.html

Electric cookers 

An induction cooker transfers electrical energy by induction from a coil of wire into a metal pot. It is more energy-efficient than other electric cookers. It allows excellent temperature control also. Water heaters, kettles, hot plates and rice cookers could be easily replaced with a programmable induction cooker. An induction coil mounted inside the cooker passes a large alternating current. The changing magnetic field induces an electrical current (eddy current) in the pot. The eddy current, flowing through the electrical resistance inside the pot, produces heat.
Sours: http://en.wikipedia.org/wiki/Induction_cooking

Automation possibilities

It is frequent that forgetting switch off electrical equipment when they don’t need. Outdoor lights works during day time, fan and lights work whether no body inside the room are common examples. Modern technology shall easily utilize to automate them if you wish.
Programmable timer relays, proximity sensors along with relay modules, water level sensor with programmable relay modules are freely available and even they easily purchase online and ship to the place you wish from web sites like ebay. You may try them yourself as a trial since they are not much expensive at all from following links.
http://www.ebay.com/itm/DIN-RAIL-DIGITAL-PROGRAMMABLE-220VAC-16A-TIMER-SWITCH-350680023473?pt=LH_DefaultDomain_0&hash=item51a62881b1
http://www.ebay.com/itm/IR-Infrared-Save-Energy-Motion-Sensor-Automatic-Light-Switch-/370689906940?pt=LH_DefaultDomain_0&hash=item564ed718fc
http://www.ebay.com/itm/PIR-switch-Human-infrared-sensor-Sensor-switch-Microwave-radar-sensor-switch-/400439037871?pt=LH_DefaultDomain_0&hash=item5d3c06cfaf

Lighting

It is clear that incandescent lamps are highly in-efficient. Light Emitting Diode (LED) the latest technology for the lighting and LED bulbs are even more energy-efficient and more durable than Compact Fluorescent Light (CFL) bulbs. Even though LED requires less wattage than CFL for the same amount of light, using CFL bulbs are still worth with considering capital investment and the quality of the light.  For a comprehensive, study the data given in Table_01.
For sensitive lighting requirement such as industrial application, T5 fluorescent tube lamps driven by electronic ballasts are ideal. T5 lamps are both electrically and physically incompatible with T8 and T12 fluorescent lamps. T5 fluorescent is the first linear lamp type to be served only by electronic ballasts. It is smaller than T8 and T12 lamps, and efficacy is very near to LED lamps.
References: http://www.bulbamerica.com/wattage-lumens-brightness.html, http://news.cnet.com/8301-11128_3-20087668-54/side-by-side-led-cfl-and-incandescent-bulbs/

Televisions

LED television more energy efficient, provides a brighter display and provides better contrast than a LCD television. LED TV uses light-emitting diodes for backlighting versus CCFLs used by LCD TVs. It has thinner panel, and lesser heat dissipation. The display of an LED TV is also a LCD one, hence technically it would be cold "LED-backlit LCD television"
Reference: http://www.geeky-gadgets.com/the-difference-between-lcd-and-led-tvs/

Water pumps

Submersible type pumps are more efficient than suction type pumps. Motor specification varies with the application. Head, pumping capacity, pumping diameter and output power are the key factors needs to examine. Two water level sensors along with programmable relay switch could be used to automate the motor to avoid tank overflows and tank becomes empty.

Electricity shall use for mandatory requirements during system peak

It is oblivious that generation cost of electricity is higher during the system peak around 6.30pm to 9.30pm since thermal power plants are dispatching to meet the demand. More electricity consumption in peak results more generation cost for the utility. Finally it is reflected to the electricity tariff. Since control electricity during peak is not affecting the consumer’s electricity bill directly, it may favorable for the tariff increments.

SRIPADA UDAMALUWA PROJECT

SRIPADA is the most sacred place for the Buddhists. Official Sripada season begins in December and ends in May. During the season, for a day, there are more than 100,000 pilgrims arrive to Udamaluwa. It is anticipated around 20 million of pilgrims venerate Sripada during a six month of the season. Existing electrical system of Sripada is not energy efficient, reliable and a safe one. 

Also the Required lighting level to the floor area has not fulfilled with the existing lighting system. Since, Halogen lights have been used for lighting energy efficiency of the system is very low. Lighting protection system also is not reliable, there were several numbers of lightnings attacks and they were damaged some equipment. 

Hence energy efficient quality lighting system could be designed. The appropriate outdoor lighting level which is suitable for a religious place should be maintained. Lighting design as it applies to the built environment, also known as “Architectural lighting design” is both a science and an art. 

Lighting of structures must consider aesthetic elements as well as practical considerations of quantity of light required, occupants of the structure, energy efficiency and cost. Here the light fittings arrangement should not be disturbed to the aesthetic beauty and the sacredness of Sripada. Cool and calm feeling would be given to the people by the lighting arrangement. LED lamps has been selected for the Udamaluwa outdoor lighting design, since it is the current highly energy efficient lighting technology.

Research on Electricity Subsidies in Sri Lanka

A subsidy is assistance to a business or economic sector or producers. Most subsidies are set in place by the government for producers or are distributed as subventions in an industry to prevent the decline of that industry. Subsidies are one powerful policy tools in the hands of the government to rectify the economic and social impacts. In many countries used subsidies for decades to achieve a range of economic, social and environmental objectives. Indeed, one of the most challenging responsibilities of a government is allocating financial resources to achieve public good. There are number of criteria by which a subsidy policy may be assessed. Sometimes it may be serving a public, rather than a private interest. Sometimes it may be achieving its intended objective efficiently, whether it has any negative, unintended consequences, such as corruption or environmental degradation. Only when citizens are in possession of this information can they make an informed decision on whether their government is spending money wisely.

The focus of this research is to find the negative impacts of electricity subsidy in Sri Lanka. In addition to forming a large part of government expenditure in Sri Lanka, subsidies for electricity have a tremendous impact on the lives of citizens. At the most immediate level, these subsidies affect how much people pay for energy. But digging deeper reveals that they have a profound effect on the environments in which people live and the economies in which they earn their living.

The system for providing electricity subsidies is more complex than other products, since policies and tariff rates on electricity differ between consumer categories and among different blocks. Moreover, state governments not only provide subsidies on tariff rates (by providing electricity to consumers at discounted rates), but also grant capital subsidies to the state utilities. The utilities then approach the state government and the respective state electricity regulatory commissions for approval of the tariff rates. The final seal of approval is provided by the regulatory commission called Public Utility Commission of Sri Lanka (PUCSL). The approved tariffs are often lower than those petitioned for by the utilities. This markdown is done with the aim of meeting social and development objectives for different consuming categories.

In Sri Lanka block tariff structure is applicable to domestic electricity consumers. Each block is consisted 30 kWh. Average consumer details taken of the country are given below. These data has been extracted from the consumer details of Ceylon Electricity Board in 2012.

Blocks	Average No of Consumers	Consumer Percentage in Blocks	Consumption (kWh Units)	Consumption Percentage	Average Charge per Account  (Rs)	Actual Cost (Rs)
Units <= 30	818,374	19.68%	15,488,111	5.40%	78.02	397.43
30 > Units <= 60	1,257,004	30.23%	56,780,577	19.80%	237.41	948.60
60 > Units <= 90	1,136,860	27.34%	84,574,379	29.49%	518.92	1,562.25
90 > Units <= 120	512,048	12.32%	52,291,083	18.23%	1,162.83	2,144.55
120 > Units <= 150	217,271	5.23%	28,582,917	9.97%	2,064.88	2,762.64
150 > Units <= 180	98,819	2.38%	15,951,746	5.56%	3,107.53	3,389.90
Units > 180	117,134	2.82%	33,143,785	11.56%	6,864.23	5,942.08
Total	4,157,510	100.00%	286,812,598	100.00%

According to the above data first four blocks are receiving electricity subsidy. Consumer in blocks over 120 units of electricity charged more than amount the consumed. The consumption pattern among these consumers and electricity equipment are different. To have an idea of distribution of energy inefficient apparatus usage a data survey has been done. Incandescent lamp is the common energy inefficient equipment in Sri Lanka. As a pilot project sample data has been collected from a randomly selected houses in Kahawaththa DS Division. These sample data can be used for a prediction of whole country. The data collected format and the calculation is given below.  

No	From	To	Incandescent Lamps							Energy saving (kWh)
			15 W	25 W	40 W	60 W	100 W	Total (W)	Possible Saving (W)
1	17:30	18:30			1	1		100	80	0.24
2	18:30	21:30			2	2		200	160	0.48
3	21:30	06:00			1			40	32	0.272
										0.992

Energy consumption of CFL lamp (5 stared rating) is about one fifth of the consumption of incandescent lamp. Quantify the electricity wastage caused by energy inefficient equipment. Hence 80% of power could be saved by using CFLs instead of incandescent. Consumption pattern and usage among different tariff blocks were investigated from random sample of 648 houses. Then the data sorted for the blocks and got the sum of demand saving and the energy saving. The summary of the data survey is given below. Average possible demand saving for a individual consumer of a given block per day and Average Energy saving per day by a individual consumer in a given block has been calculated.

Block	Consumers	Possible demand Saving (W)	Average demand Saving (W)	Energy Saving (kWh)	Average Energy Saving (kWh)
Below 30	162	14,077	87	61.56	0.38
31 to 60	276	31,035	112	132.78	0.48
61 to 90	170	19,616	115	84.57	0.5
91 to 120	26	3,146	121	18.93	0.73
121 to 150	12	1,148	96	5.23	0.44
151 to  180	2	75	38	0.23	0.11
Total	648	69,097		303.3

Those data can be extended for the country values since the total number of consumers in each category is known. The predicted possible energy saving for the country would be shown in below.

Category	Average consumers in the population	Possible saving per one consumer (kWh)	Possible saving (MWh)
Below 30	818,374	0.38	310.98
31 to 60	1,257,004	0.48	603.36
61 to 90	1,136,860	0.50	568.43
91 to 120	512,048	0.73	373.8
121 to 150	217,271	0.44	95.6
151 to  180	98,819	0.11	10.87
Total			1,963.04

According to the Poverty Indicators on Household Income and Expenditure Survey - 2009/10, (Volume 1 - Issue 2) published by Ministry of Finance and Planning on May 2011  latest calculation of poverty indices shows that poverty level of  the country is 8.9% and Ratnapura District is 10.5%. Then the estimated energy saving  is about 1.7 GWh. However the average daily energy consumption in Sri Lanka is about 30 GWh as per "Generation Statistics “ of Ceylon Electricity Board. Hence the possible energy saving is about 5.7 %.  Further the average generation cost around *Rs. 18 per kWh. Then eestimated saving would be about Rs. 30 million per day.

Similarly the peak demand reduction also could be predicted as follows. The actual value would be less than the predicted value. To rectifier the error 0.7 factor could be introduced. Then the possible demand would be around 300 MW.

Category	Average consumers in the population	Possible saving per one consumer (W)	Possible saving (MW)
Below 30	818,374	87	71.2
31 to 60	1,257,004	112	140.78
61 to 90	1,136,860	115	130.74
91 to 120	512,048	121	61.96
121 to 150	217,271	96	20.86
151 to  180	98,819	38	3.76
Total			429.30

Predicted daily demand curve is shown below. Normal daily demand curve has been extracted from system control data of Ceylon Electricity Board.

Intention for the electricity subsidy is lack of intelligent of reality. It is clear that 90% of electricity wastage due to energy inefficient equipment is responsible subsidized electricity users.  By other hand objectives of electricity subsidies are not achieved. As a result Government has to bear the unnecessary burden of wasted energy inside the subsidized electricity consumers since electricity subsidy encourages the usage of energy inefficient equipment. In the country view, it is wide to provide subsidy on energy efficient equipment such as CFLs and promoting LED lamps for street lighting to minimize the electricity wastage.

References

Ø    Domestic consumer account details, Billing Section, Ceylon Electricity Board.

Ø    Generation Statistics - 2011, Ceylon Electricity Board.

Ø    Energy consumption specification and cost of incandescent and CFL manufacturers.

Ø    Tariff details, Public Utility Commission, Sri Lanka.

Ø    System Control data of daily demand curve, Ceylon Electricity Board.