When factories purchase LPG by kilogram (kg) and CNG by standard cubic meter (Sm³), comparing the costs of these two fuels directly is not meaningful. MMBtu (one million British Thermal Units) is the internationally recognized unit of thermal energy that converts different fuels into the same energy basis, allowing manufacturers to compare their actual energy costs and prepare more accurate energy budgets.

This guide explains the process step by step—from energy conversion formulas and calculating VND/MMBtu to a practical budgeting example for a textile dyeing factory.

What Is MMBtu and Why Should Manufacturers Use It?

BTU (British Thermal Unit) is a unit of heat energy, defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. MMBtu, equal to 1,000,000 BTU, is the standard energy unit widely used in the industrial gas industry.

Conversion Formula and Example Using 100 Tons of LPG

Table 1. Heating Value Conversion Factors for Industrial Gases

Source: DATA Energy, compiled from ISO 13686 and industry standards.

Example: How Many MMBtu Are in 100 Tons of LPG?

100 tons of LPG = 100,000 kg, 100,000 × 0.04686 = 4,686 MMBtu

Therefore,

100 tons of LPG ≈ 4,686 MMBtu

To determine how much CNG provides the same amount of energy:

4,686 ÷ 0.03378 = 138,692 Sm³ of CNG

Alternatively, you can use the online Energy Conversion Calculator available on the DATA Energy website.

Calculating Fuel Cost in VND per MMBtu

The general formula is:

Cost (VND/MMBtu) = Purchase Price (VND per Unit) ÷ MMBtu Conversion Factor

Table 2. DATA Energy CNG Prices – January to August 2026

Source: DATA Energy (dataenergy.com.vn). Prices exclude VAT. CNG prices for month n are calculated based on the Dated Brent price of month n−1.

Example: August 2026 CNG Cost

August 2026 CNG Price: 17.83 USD/MMBtu × 26,000 VND/USD ≈ 463,580 VND/MMBtu

How Do Manufacturers Use MMBtu in Practice?

Monthly Energy Budgeting

Instead of budgeting fuel consumption in kilograms or cubic meters, manufacturers can budget in MMBtu. When fuel prices fluctuate, only the VND/MMBtu price needs to be updated, while energy consumption remains unchanged if production volume stays constant.

Comparing the True Cost of LPG and CNG

Converting both fuels to VND/MMBtu enables manufacturers to identify which fuel delivers lower energy cost without being misled by different sales units.

Monitoring Energy Efficiency

Tracking MMBtu per ton of finished product is an important energy performance indicator that helps identify declining burner efficiency or abnormal energy consumption in production processes.

Case Study: Fuel Budget for a Textile Dyeing Factory Using 80 Tons of LPG per Month

A textile dyeing factory in Binh Duong Province consumes 80 tons of LPG per month. The purchasing department wants to prepare the fuel budget for August 2026 and evaluate whether adding CNG as a backup fuel would reduce operating costs.

Table 3. August 2026 Fuel Budget Comparison

*Estimated LPG price based on the August 2026 CP price of USD 630/ton and an exchange rate of 1 USD ≈ 26,000 VND. The August 2026 CNG price is based on the July 2026 Dated Brent price of USD 83.41/barrel. Figures are for illustration only. Please contact DATA Energy for an official quotation.

Important Note

In 2026, LPG prices were unusually higher than CNG due to geopolitical tensions in the Middle East and supply disruptions affecting the Strait of Hormuz, which significantly increased the Saudi CP benchmark.

Under normal market conditions, LPG may be cheaper than, similar to, or more expensive than CNG depending on market dynamics. Therefore, August 2026 should not be used as a long-term benchmark for fuel selection.

The purpose of this example is to demonstrate how to calculate fuel costs using MMBtu, not to recommend one fuel over another.