CENTER OF EXCELLENCE FOR ENERGY EFFICIENCY

According to the document "Energy mapping user guide – Draft" of the Vietnam - Denmark Energy Partnership Program for the period 2020 – 2025 (DEPP3), “energy mapping” is a tool that illustrates the relationship between energy supply and energy use levels within a company’s operating system in the industries.

“Energy mapping” provides a comprehensive and detailed view of the energy flow throughout the plant, helping to determine the energy consumption hotspots, thereby allowing the enterprises to prioritize intervention solutions based on practical data. Additionally, it also provides baseline data for developing energy efficiency solutions, planning energy strategies, and reducing the company’s energy-related CO₂ emissions.

During the site visit on October 9 to enterprises that have signed and achieved results in implementing the Voluntary Agreement Scheme on Energy Efficiency in Energy Intensive Industries (VAS Program) of DEPP3, energy auditors shared their findings from applying this new tool.

At the Hanoi Beer - Alcohol - Beverages Investment Development Joint Stock Company (HABECO-ID), Dr. Trinh Viet Thieu - an expert from PolyTechnical Energy and Environment JSC (POLYTEE), the unit conducting the factory’s energy audit - stated that according to the energy mapping developed with support from Danish experts, the brewing process is the largest heat energy consumer, using nearly 10 million kWh per year. Furthermore, the fermentation and cooling stages were also identified as the most significant sources of cooling energy consumption.

Based on the audit results, the expert team identified seven promising energy efficiency solutions for the factory.

One of these - replacing old, low-efficiency coal boilers with high-efficiency biomass boilers - has already been approved for investment and installation by the board of directors (BOD), scheduled for the end of 2024. This solution targets HABECO-ID’s biggest energy hotspot, with an investment of VND 15 billion, a payback period of 4.7 years, and is expected to cut about 536 tons of coal while reducing CO₂ emissions by 980 tons per year.

Six other solutions - such as utilizing cold gas discharged from CO₂ evaporation to cool NH₃, using Ewater descaling equipment to remove dirt and enhance the heat exchange efficiency of the cooling tower, installing economizer to use heat from boiler exhaust gas, etc. - are being considered by HABECO-ID for future implementation.

If all seven solutions are fully implemented, the factory will cut its total energy consumption by 25.4% and CO₂ emissions by 20.5% compared to before. For a factory with a designed capacity of 50 million liters of beer per year, this is a huge and impactful number, especially since the factory’s current energy consumption (228 MJ/hl) is higher than the industry standard (196 MJ/hl) and relies heavily on coal fuel. In the 2021-2023 period, HABECO-ID had to spend VND 10-15 billion annually on coal.

“The detailed energy audit and energy mapping give us an overview to advise HABECO-ID on technical solutions and investment efficiency calculations,” said Dr. Thieu. Since Circular 25/2020/TT-BCT on conducting energy audits has not included this tool, Dr. Thieu recommends making energy mapping a mandatory part of the Circular “to achieve better energy audit effectiveness.”

Mr. Tran Dang Tuan, Deputy Director of HABECO-ID, recognized that participating in the VAS Program helped them approach energy management more systematically, and the solutions proposed by the Program helped them improve production efficiency. At the same time, he affirmed the green and sustainable development orientation that the company is pursuing.

Sharing with Science and Development Magazine, Dr. Trinh Viet Thieu admitted that creating energy mapping is not easy as factories lack sufficient energy data.

“Factories in Vietnam usually only know the total energy input and output, not the detailed figures for each intermediate stage. Each factory is a complex combination of many stages, so to create an accurate and effective map, we must use good measuring and monitoring equipment to continuously track the factory’s operations for several months, or even a year. However, once the energy map is available, it will be easier in subsequent years to monitor which stage is having energy efficiency issues to intervene,” he said.

Dr. Thieu concluded that there are three factors to consider to improve the quality of energy mapping in particular and energy auditing in general: tools, people, and report quality.

Accordingly, instead of using the energy figures on the equipment labels in the factory, modern measuring instruments (such as power analyzers and ultrasonic leak detectors) must be used to collect actual data, thereby detecting energy issues.

Secondly, regarding energy audit activities, enterprises only comply with the minimum requirements, ignoring the potential for long-term efficiency improvement and cost savings that thorough energy audits can bring. The solution is to establish a joint audit team including external experts and internal staff to ensure effective cooperation, full data access, and increased commitment to the audit results.

The final factor is report quality. Previous energy audit reports could be lengthy or unclear, making it difficult for the BOD to make decisions. However, when presented in concise, clear summary tables, illustrated with energy maps, linking issues directly to solutions, and including key financial indicators such as investment amount, energy efficiency, and payback period, these reports will be very helpful to the BOD.

Based on practical experience with HABECO-ID and Polytee under the VAS program, Dr. Thieu proposed three recommendations to scale up energy audits in Vietnam: (i) updating Circular 25/2020/TT-BCT to make energy mapping mandatory; (ii) organizing in-depth training for energy auditors and factory energy managers on advanced energy mapping techniques and the use of modern measuring equipment, and (iii) connecting high-quality energy audit activities (including energy mapping) with preferential green finance programs and other investment incentive policies.

The goal is to encourage enterprises to invest in in-depth audit activities, thereby developing financially feasible energy efficiency projects.