Methane takes up about 1.5 cubic meters per kilogram at room conditions. These guides cover the three ways to shrink it into a tank and what each one costs in weight, energy and hardware.
Adsorbed natural gas storage puts a porous solid inside the tank, which then holds four to five times more methane at 35 bar than the empty vessel would. The heat, the leftover gas and the packing density are where the engineering gets hard.
An 80-liter steel cylinder at 200 bar holds about 13 kg of methane and weighs over 100 kg empty. Every later design of CNG storage tanks, from carbon fiber wraps to vacuum jackets, tries to change that ratio.
Both fuels are the same methane. One is squeezed to 250 bar, the other cooled to −162 °C, and that single choice decides tank size, station cost and which trucks each one suits.
Raw biogas from a landfill is barely half methane. Cleaned up to pipeline quality, it becomes a fuel that fills the same CNG cylinders and LNG tanks as fossil gas, with a very different carbon score.
Burned, natural gas releases about 43% less carbon dioxide than coal for the same energy, the basis of its name as the cleanest fossil fuel. Leaked, its methane traps heat about 30 times more strongly than CO2 over a century. Both facts belong in the answer.
A cylinder filled to 200 bar at 15 °C holds about 168 grams of methane per liter of internal volume. Cooled to its boiling point of about −162 °C, the same liter holds roughly 420 grams as a liquid. Packed onto the inner surface of activated carbon at 35 bar, it can hold around 100 grams, about four times what the empty vessel would carry at that pressure. Those three numbers frame almost every design decision in gas storage.
Compression is the established route for vehicles and for most stationary buffers, and its hardware is standardized down to the cylinder class. Liquefaction wins where range matters more than simplicity, on long-haul trucks, ships and export terminals, and accepts that the liquid slowly warms and boils off. Adsorption sits between them: lower pressure, simpler compressors and tanks that can take flatter shapes, at the price of heat management and a fraction of gas that stays in the pores at the end of discharge.
The adsorbed natural gas guide explains how porous solids hold methane and why the field has chased the 180 V/V target for decades. The guide to storage tanks covers Type I to Type IV cylinders, the standards they are built to and how to turn a water volume into kilograms. CNG vs LNG sets compression and liquefaction against each other for real duty cycles, and renewable natural gas shows that biomethane uses exactly the same storage chain. For the case for gas as a fuel at all, including its methane leakage problem, read is natural gas clean.
Storage happens at very different scales. A car cylinder holds a few dozen kilograms, a station cascade a few hundred, and a tube trailer several tonnes. At the other end, the gas grid itself relies on underground storage: depleted fields, aquifers and salt caverns that are filled in summer and drawn down in winter. The United States alone operates close to 400 such sites, according to the Energy Information Administration. The guides in this section concentrate on the smaller vessels, where density and weight matter most.
Whatever the scale, comparing options by volume alone misleads. A tank's usable energy depends on the pressure it starts at, the pressure the engine or network needs and, for adsorbed gas, how much stays behind in the pores. The tank capacity calculator works through these numbers for a chosen volume and pressure.
LNG, by a wide margin. A liter of LNG holds about 420 grams of methane, a liter of cylinder at 200 bar and 15 °C about 168 grams, and a liter of carbon-filled adsorbed tank at 35 bar around 100 grams.
LNG has to stay near −162 °C. A parked car's tank slowly warms and the liquid boils off, so LNG suits vehicles that run every day and use their fuel quickly, such as long-haul trucks.
Volume per volume: how many liters of gas, measured at standard temperature and pressure, a tank holds for each liter of its own internal volume. It is the usual way to compare adsorbents with compressed gas.
Mostly underground, in depleted oil and gas fields, aquifers and salt caverns, which buffer seasonal demand. LNG import and export terminals add large insulated tanks above ground.
No. Once biogas is upgraded to biomethane it is chemically the same fuel as fossil natural gas and uses the same cylinders, tanks and storage methods.