The first question is how much power do Chinese outdoor LED displays consume in 1 year?
Let’s first see how many outdoor LED displays have been installed in China.
Table 1: Chinese LED Display Enterprise Sales from 2010 to 2014 (RMB 1 billion）
Note: Table 1 data is from Report on China’s LED Display Industrial Development in 2014 delivered by Guan Jizhen, Chairman of LED Display and Application Association.
As per the Report on China’s LED Display Industrial Development in 2014, 80% of Chinese LED display enterprises’ total sales are LED displays and the rest are from LED lighting and other products. 60% of LED display sales are outdoor LED displays, and the rest are from indoor LED displays.
Therefore, cumulative outdoor LED display sales from 2010 to 2014 is (19+22+25.3+27.0+30.2) *82% *60% = RMB60.8 billion
Most outdoor LED displays sold from 2010 to 2014 have been installed and are operational. During this period, average outdoor LED display price is about RMB 5,000/ m2, and approximately 120 million m2 outdoor displays were installed in China
Let’s calculate China’s outdoor LED displays’ power consumption.
Number of cases
Table 2 is a chart on Chinese outdoor LED display cases published by a professional LED display media company. Based on above data, we can see that number of LED displays with 16mm pixel pitch (physical distance between LED pixels) is about 45% of total displays. As average power consumption for outdoor LED displays with different pixel pitch differs slightly under same luminance, we have decided to use P16 (16mm pixel pitch) to simplify the following deduction and calculation.
Four representative domestic listed companies P16 outdoor LED display products are used as examples (products with 16mm pixel pitch, using parameters listed on corresponding companies’ official websites, as on October 2015).
Table 3: Average power consumption of four listed
companies’ conventional P16 products
To simplify calculations, we will take 272 W/m2 as average power consumption for the four representative listed companies’ P16 products. Assuming daily working hours is 14 hours, and total mounted outdoor LED displays in China is 12 million m2, approximate power consumption will be 16.7 billion kWh, i.e., annual power consumption of Chinese outdoor LED displays is about 16.7 billion kWh.
To intuitively understand power consumption, we will compare it to Three Gorges Dam’s output.
In 2014, Three Gorges Dam’s total annual power output was 98.8 billion kWh, with about 270 million kWh output per day. China’s installed outdoor LED displays’ annual power consumption is 16.7 billion kWh, approximately equivalent to Three Gorges Dam’s 60 days output, 8.5 million tons raw coal consumption, and 17 million tons carbon dioxide emission. If you think about the intense smog and hazy weather we have in cities, you will realize that outdoor LED displays are one of the causes.
The next question is, can we stop using outdoor LED displays as they consume so much power?
In this internet era, more and more outdoor images and video advertisements, and dynamic outdoor information need to be displayed, which cannot be achieved by traditional printed billboards. At present, only outdoor LED displays can fulfill this need. According to the Report on China’s LED Display Industrial Development in 2014, outdoor LED displays’ average annual growth rate from 2000 to 2014 is about 50%, showcasing the social value created by outdoor LED displays and their usage trend.
Therefore, although outdoor LED displays’ power consumption is excessive, we cannot give up, but instead have try to find power saving methods.
How can outdoor LED displays save power? Industry experts give the following suggestions:
1. Use high-efficiency LEDs and superior LED chips
2. Use high-efficiency power supply switch to effectively promote power conversion efficiency
3. Adopt perfect thermal design for screen cabinets to reduce power consumption from fans
4. Use comprehensive scientific circuit design to cut down internal circuit power consumption
5. Automatically adjust LED display luminance based on changes in external environment.
The above 5 measures can help drastically reduce outdoor LED display power consumption. At the same time, improved efficiency and reduced heating in outdoor displays will lower LED light decay and increase service life.
As Absen’s X16 outdoor LED displays strictly adhere to the first four measures listed above, their power consumption is about 133W/m2, about half of 272W/m2, the four listed companies’ P16 products’ average power consumption. Absen X16 products are comparable to U.S. based DACTRONICS similar outdoor products in power savings, which is a top level internationally.
If all of China’s outdoor LED products are replaced with Absen X16, annual power consumption can be reduced by 8.5 billion kWh, freeing up Three Gorges Dam’s 30 days power production, and reducing 4.25 million tons raw coal consumption and about 8.5 million tons carbon emissions. This way, we can bring back white clouds to the blue sky.
Let’s calculate the financial benefit: If an advertiser buys 300 m2 X16 (P16) products, and industrial power consumption charges are assumed to be at RMB 1 kWh, with working hours at 14 hours per day, then power charges saved is 300× (272-133) × 0.001× 14= about RMB 600 per day and RMB 1.28 million every 5 years.
Chinese outdoor LED displays’ annual power consumption is 16.7 billion kWh, approximately equivalent to Three Gorges Dam’s 60 days’ power production, 85.5 million tons raw coal consumption, and 17 million tons carbon emissions. Absen X16 products can save 50% power, i.e., Three Gorge Dam’s 30 days’ power production. If advertisers buy 300 m2 Absen X16 products, there will be RMB 1.28 million power savings over 5 years. So, what should we choose as socially and environmentally conscious citizens?