Background:

Cambodia is a tropical country in Southeast Asia with extreme heat waves sweeping across the country during the dry season. This results in the lack of hydropower which causes power shortages in Cambodia. Power shortages during the dry season shortens the lifespan of lead-acid batteries, which may lead to network availability issues. Smart Axiata, Cambodia’s leading mobile telecommunications operator, is part of Axiata Group Berhad, one of Asia’s largest telecommunications groups.

1. Commercial Value

As we move into the LTE-A and 5G era, the power consumption of wireless base stations is expected to significantly increase which brings new challenges to mobile operators, including Smart. Take one base station as an example:

• To provide continuous mobile broadband services to consumers, a 5-hour backup is designed for Site A. Due to the increase in power consumption of the site to 5kW, 800Ah lead-acid batteries is required. However, this leads to loading and/or space issues at rooftops in dense urban areas as the combined battery weight will be more than 1 ton.
• Lead-acid batteries have shorter lifespans compared to BoostLi. Furthermore, the capacity of lead-acid batteries will discharge faster during poor electricity conditions.
• 5G radio units consume much more power than previous technologies. Thicker power cables are needed to provide enough power to the 5G radio unit but this will lead to a load issues and is more expensive.

Figure 1: Rooftop Site A with Lead-acid Batteries

2. Solution and Benefits

Smart uses Huawei's BoostLi intelligent telecom lithium battery – as a replacement to traditional lead-acid batteries. With a proposition of being "Simple", "Intelligent" and "Green", BoostLi helps Smart mitigate power shortage challenges .

2.1 Reliable Power Backup

BoostLi batteries have better adaptability to poor power grid situations by maintaining better SOH and backup time compared to lead-acid batteries. The solution significantly improves network availability. In a poor power grid scenario, the usual service life of lead-acid batteries is only around 2-3 years, while the service life of BoostLi could reach to more than 5 years. Hence, companies can save up to 20-30% on battery investments annually.

Figure 2: BoostLi Deployed at Site A

2.2 High Density

BoostLi has better energy density compared to traditional lead-acid batteries. As an example, a 100Ah BoostLi is 60% smaller and 70% lighter compared to a traditional lead-acid battery. If the load of the base station is 5kW, the required backup time is 5 hours and consequently, the weight of the lead-acid batteries will be more than 1 ton. However, the load will only be 0.43 ton if BoostLi is deployed. This avoids the need for site reinforcement and/or reconstruction of rooftop sites, which then leads to cost savings and shortening of TTM.

2.3 Intelligent Voltage Boosting

BoostLi contains a built-in intelligent booster which can support 57V DC constant output for 5G radio units. With this feature, thinner power cables can be used for future 5G radio units. Assuming the required power cable length of a site is 50 meters, the intelligent boost feature of BoostLi coupled with a thin cable can reduce power cable investment by 60% and weight by 60% compared to the traditional solution of thicker power cables (2*10mm^2).

3. Conclusion

By collaborating on new technological innovation such as BoostLi, Huawei and Smart are able to mitigate power shortages in Cambodia while providing better mobile broadband network availability to Smart’s customers. Besides saving some costs, Smart’s decision to deploy BoostLi also results in many of their sites having the ability to support future 5G technologies.