Taiwanese Marts Take a New Course on Energy Conservation

By HORNG-CHING HSIAO, HUANG-SHEN GUO, and FU-SHENG SUNG

Last year, Taiwan's top nine retail marts together operating 123 stores across the island signed voluntary agreements on energy efficiency with the Ministry of Economic Affairs (MOEA), pledging to trim 7% from their total electricity bills in three years. All are getting a helping hand from energy-saving programs, including training from the non-profit Taiwan Green Productivity Foundation (TGPF). They also hope to inspire others along the road to greener business.

The voluntary agreements are expanded from similar pacts the MOEA inked with the island's top five convenience store chains in 2006. The top five chain-store groups vow to reduce electricity usage by an average of 6.2% over three years ending in 2009, including a 3.2% cut in the first year that will cut electricity demand by an estimated 43.68 million kilowatt/ hours.

The 2006 and 2007 agreements differ in that the latter adds assistance to participating groups. TGPF organizes groups within enterprises to carry out various energy-saving programs. The groups help identify sources of energy waste through inspections and diagnosis and offer energy-efficiency assessment and improvement planning.

The 2007 agreement aims to pare electricity demand by 5-8% island-wide in three years, saving an equivalent of 60 million kilowatt hours. This will cut energy costs by NT$120 million (US$4 million at US$1:NT$30) and reduce carbon emissions by an estimated 37,000 metric tons. Best of all, investment in efficient lighting products can be recouped in three years, saving an estimated NT$240 million (US$8 million).

The top nine marts, with a total of NT$160 billion (US$5.3 billion at US$1:NT$30) in annual revenue, offer pleasant shopping environments and a broad selection of merchandises at their stores. Lighting and air-conditioning systems at their massive-area stores, however, burn up an enormous amount of electricity.

Statistics compiled by the MOEA's Bureau of Energy show that electricity use in Taiwan has grown at annual pace of 4.7% over the past five years, with mart stores sucking up a good share of the total. The stores consume 341 kilowatt hours per square floor meter a year, on average, more than double the amount for office buildings, according to bureau's figures.

To tackle this situation, the MOEA signed agreements with the retail marts. Through the program, the ministry hopes to prod Taiwan closer to the goal of sustainable-development, while meeting targets under the Kyoto Protocol and preparing the island for the age of high energy prices.

Shopping for Solutions

According to figures compiled by TGPF for the year to March 2007, Carrefour, RT-Mart, Far Eastern Geant, Costco President, Taisuco, Dollars, Megaful, B&Q and Tsann Kuen jointly consumed 890 million kilowatt hours of electricity at their total 123 stores, accounting for 3.9% of the total electrical power consumed by the island's commercial segment as a whole. B&Q and Tsann Kuen are household-appliance retailers while the other seven are general-merchandise retailers.

Table 1: Taiwan's Retail Marts and Store Electricity Consumption

Classification	General Mart							Household Appliance Mart		Tota
Mart Name	Carrefour	RT-Mart	Far Eastern Geant	Taisuco	Costco President	Megaful	Dollars	B&Q	Tsann Kuen
No. of Stores	47	19	15	4	4	7	3	21	3	123
Electricity Used (10 million kilowatt hours/year)	40.2	16.74	11.16	3.19	3.18	3.15	2.48	7.15	2.07	89.3

Source: Taiwan Green Productivity Foundation

Note: Figures for the year ending in March 2007

According to studies by the foundation, an average mart store offers massive shopping areas, spacious parking lot and less expensive merchandise. Such stores can consume a tremendous amount of electricity. For instance, a newly opened five-story store run by a certain retailer consumes 14.14 million kilowatt/ hours of electricity a year. The building has 44,826.75 square meters of floor area including the 25,999.75 square meters of basement area and 18,827 square meters of air-conditioned space.

The top nine marts can be categorized into general retailers and household-appliance retailers. Their power-consumption percentage by individual electrical devices, power-consumption intensity by unit floor area and average electricity spending are as follows:

Power-consumption percentage by individual electrical equipment: For general stores air-conditioning system accounts for 35.2%, lighting 26.3%, power outlets 5.1%, elevators 5.3%, freezers and refrigerators 16.6%, and other 11.5%. For household-appliance stores, air-conditioning systems make up of 49.2% of total electricity consumption, lighting 34.7%, electrical outlets 8.3%, elevators 3.6% and other 4.2%. In both categories, therefore, air-conditioning systems are the biggest electricity hogs, followed by lighting.

Power consumption intensity by unit area size: For general stores, the intensity is 341 kilowatt hours per square meter a year for shopping and parking areas combined. For household-appliance stores, the intensity is 360 kilowatt/ hours per square meter. By demand use intensity (DUI), the average number for general store is 70 watts per square meter and 71 watts per square meter for household appliance store. In this comparison, the difference between the two categories is slight.

Average electricity spending: For general stores, the electricity costs an average of NT$1.91 per kilowatt/ hour; while household-appliance stores pay NT$2.06 per kilowatt/ hour. Both levels suggest that electricity is still too cheap in Taiwan.

Table 2: Taiwan's Top Nine Retail Marts and Their Energy Use Intensity (EUI) Values

Mart Type	Store Number	EUI Excluding Parking Area's Value		EUI Including Parking Area's Value
		Rang	Average	Range	Average
General Store	99	472~770	631	236.5~382.4	341
Household Appliance Store	24	304~494	399	256.7~464.1	360

Note: The EUI measurement unit is kilowatt/ hour per square meter a year.

Even though European and American marts have operated in Taiwan for many years and grown considerably in terms of operation size after years of adaptation to local environment and management, lighting at the stores is still blamed as the top electricity guzzler as a result of Taiwan's long absence of guidelines and advice for efficient lighting. Throughout the island, lighting fixture formats and installation arrangements at mart stores are roughly same. For instance, they mostly use 110W fluorescent tubes, compact fluorescent lamps and metal halide lamps at shopping area as well as metal halide lamp and halogen spotlights for signboards. On average, a mart store's luminance is 750 to 1,000 lux, apparently far more than needed.

Behind the excessive lighting electricity are four shortcomings:

1. The stores usually lack windows that could admit natural light.

2. The stores largely use the less expensive but power-hungry incandescent lamps and halogen lamps as spotlights due to their better visual effect.

3. Store owners generally know little about lighting quality and therefore often use inefficient lamps and inductor-type ballasts to cut up-front costs, at the cost of higher future energy bills and flickering lights.

4. Lighting systems are not equipped with density controllers so that electricity is burned at same rate during peak and off-peak hours.

Bright Ideas for Power Savings

An ideal design for store lighting should involve natural light through greater use of patios and windows. Light-density controllers are another way to help stores cut their lighting bill.

In addition, efficient light sources accompanied by electronic ballasts will ensure lighting quality at lower cost and level of electricity consumption.

An efficient light consists up of efficient light source and lighting fixture with good reflective qualities. Coupled with energy-saving devices, like electronic ballasts and electronic dimmers, the lighting system can further reduce power consumption by working more efficiently. Efficient, ecological lighting systems include T-5 fluorescent, low-power ceramic metal halide lamps, electrodeless discharge lamps and LED lamps. These lamps can cut electricity usage by up to 30% compared to traditional lighting sources.

By substituting inductor-type ballast for electronic ballast, mart stores can cut electricity consumption for lighting by at least 28%. Currently, most stores use fluorescent lamps with inductor-type ballast, which requires a starter, takes two to five seconds to light up lamps, has power factor of only 90%, comes with harmonic distortion of up to 48%, leads to low-frequency lighting blinking and generates heat up to 55 Celsius degree.

Electronic ballast, by contrast, needs no starter, lights up lamp immediately, has a power factor up to 98%, delivers harmonic distortion of barely 20%, does not cause light blinking, can work in environments with maximum humidity of 98% and maximum temperature of 55 Celsius degree, generates moderate heat, saves up to 28% of electricity, lengthens lamp lifespan, and operates quietly. What's not to like about it?

For commercial sites, using proper lighting products can help save operation costs. From cost and maintenance considerations, the primary concerns on lighting should include high efficiency, long lifespan and low installation cost. Currently, fluorescent lamps remain the major light sources for such sites. Increasingly, these sites have adopted tri-wavelength florescent lamps over mono-wavelength lamps, which are superior to the latter on energy saving (5% gain) and color rendering (Ra84 vs. mono-wavelength lamp's Ra61).

The color rendering of tri-wavelength lamps is closer to natural than that of mono-wavelength lamps, which means objects appear closer to their true color. The lamps also last more than 10,000 hours. A T5 tri-wavelength lamp at 28 watt produces 105-120 lumens per watt, 20% better than the average of 84 lumens per watt for traditional lamps.

Something to Reflect On

Lighting fixtures with grid frames are ideal for fluorescent lamp thanks to their high reflective quality. This minimizes glaring while boosting illumination efficiency. Unfortunately, most mart stores in Taiwan use coverless fixtures to cut costs at the sacrifice of lighting quality.

Now, even LCD lamps are equipped with reflective film, which has boosted illumination by 60 to 70% at fixed wattages in many cases while reducing glare. Also, the film can maintain steady light output by keeping dust off the lamps.

Electrodeless discharge lamp is an ideal lamp for store lighting. The lamp can save up to 50% of electricity and gives off 37% more illumination than traditional fluorescent lamps. Electrodeless lamps boast an average lifespan of 100,000 hours, making it more environment friendly and energy saving. The long lifespan also reduces the lamp replacement and maintenance cost.

Low-power ceramic metal halide lamps are ideal replacements for halogen lamp as spotlights. The former consumes only half the electricity used by the latter, while boasting a lifespan four times longer. Ceramic metal halide lamp has a lifespan of 9,000-15,000 hours, around 30-50% more durable than quartz halogen lamp. Its efficiency is above 90 lumens per watt, around four to nine times better than halogen lamps and incandescent lamps. Metal halide lamp's color temperature fluctuates within 200 Kelvin range throughout the lamp's service life, proving its stability. Designing lighting fixtures for the lamps is easy thanks to the lamp's compact size. Low-power ceramic metal halide lamps can slash electricity use by up to 50% in commercial applications.

With their broad color range, LED lamps are an ideal choice for commercial places requiring colorful lighting. However, the lamps are not expected to replace traditional light sources like fluorescent lamps in the near future due to their high cost, glare, and some remaining technical problems. For the time being, therefore, they are more suitable for auxiliary applications such as signboard and external outline lighting.

For mart stores, lighting control methodology varies from store to store depending on their environment. The usual methodologies are: (1) Timer: The device automatically shift lighting mode during set time in accordance with the change of lighting environment. Or it automatically switches off and on lamps depending on preset data. (2) Daylight sensor: When daylight is sufficient indoors, the sensor automatically shifts down lighting density or even switches off lamps by controlling dimmable electronic ballasts. (3) Infrared sensor: This device judges when to turn lights on and off in rooms by detecting human body temperature. The device turns on lights when sensing higher temperature and shuts them off again when the temperature drops.

Although fluorescent lamps are noted for their long lifespan, dust in the air can hurt their illumination efficiency and light output when the buildup of the small particle on lighting fixtures is considerable. Thus, fixture cleaning is important in spite that maintenance of huge-size fixtures may not be as easy as expected. Lighting designers should take this factor into account and make their products as easy to maintain as possible. Some suggestions on maintenance: (1) Regularly clean lighting fixtures and lamps to prevent dust accumulation. Replace decaying lamps gradually so that proper illumination density and energy efficiency can be maintained at workplaces. (2) Replace lamps when their brightness output is only 70% of a new bulb, a move that cuts electricity waste by at least 17%. (3) A reasonable lamp replacement cycle at stores is two years, assuming the store keeps lamps on for around 3,600 hours a year and a typical fluorescent lamp's lifespan is somewhere between 6,500 and 8,000 hours.

To push voluntary agreements on energy saving, the TGPF conducted a study of nine marts and found that the potential energy savings at seven general marts was 6.7-15.8% and the potential for the two household-appliance marts was 7.1-17.2%. The nine marts can accomplish energy saving goals promised in the agreement as long as they fully follow developed energy-saving programs to reduce electrical consumption by lighting, air-conditioners, refrigerators and freezers, and heavy-duty electrical equipment.

Table 3: Energy Saving Potential of Taiwan's Top Nine Marts

Mart Type		Heavy-duty Electrical Equipment	Lighting	Air Conditioner	Freezer and Refrigerator	Total
General-Commodity Stores	Potential %	1.1~3.2	1.6~3.0	2.8~7.0	1.2~2.6	6.7~15.8
Household-Appliance Stores	Potential %	1.1~3.2	2.1~4.2	3.9~9.8	-	7.1~17.2

As global awareness grows over of the need to cut CO2 emissions, there will be further opportunities to extend energy-saving agreements beyond the retail segment into other industrial areas. The participating chain stores and marts have shown that the program works, and they have also enjoyed significant cost savings by reducing energy use. They suggest the energy saving model they are adopting now be applied to other industries in the following eight steps.

(1) Conduct field analysis of energy-consumption status, energy-saving measures and saved amount of these industries;

(2) Hold talks within each industry to build consensus on saving measures and volume;

(3) Hold talks within each industry on the content of the voluntary agreements;

(4) Hold events for the signing of voluntary agreements;

(5) Organize intra-enterprise service group to help set up form-filling systems and offer training programs and advice;

(6) Set up ESCO and M&V testing and verification systems to help enterprises improve project results;

(7) Making the voluntary saving program known through media to attract more enterprises to join the campaign;

(8) Track program implementation and publicize results;

The government would be able to achieve its energy-saving goals by expanding energy reduction agreements to hospitals, department stores, shopping centers, hotels, and other retail and commercial environments. (April 2008)

(Note: Horng-Ching Hsiao is an electrical engineering professor at the National Taiwan University of Science and Technology; Huang-Shen Guo is a senior official of the Taiwan Green Productivity Foundation; and Fu-Sheng Sung is a senior official of the Taiwan Lighting Fixture Export Association)