Both the E-Wave and Steam Heater Pad work. But they work differently — and choosing the right one can make a significant difference to your discharge experience and overall cost.
If you're shipping viscous bulk liquids — palm oil, animal fats, tallow, waxes, or similar cargoes with elevated pour points — you already know the challenge. Cargo that arrives solidified at destination is a serious problem. Discharge becomes slow, costly, and in some cases impossible without the right heating solution in place.
Sun Flexitanks has been solving this problem for over 20 years, and today offers two purpose-built heater pad solutions: the E-Wave Heater Pad and the Steam Heater Pad. Both work. But they work differently — and choosing the right one for your cargo and infrastructure can make a significant difference to your discharge experience and overall cost.
The E-Wave is Sun's premium heating solution, built using carbon fibre technology. It sits beneath the flexitank on the container floor and heats the cargo from the bottom up — evenly and efficiently.
The key advantage of the E-Wave is speed and precision. Carbon fibre transfers heat faster than steam, and gives operators more direct control over cargo temperature. For cargoes that solidify completely when cooled — such as palm stearin, hard tallow, or certain waxes — even bottom-up heating is critical. It ensures the entire cargo mass reaches discharge temperature uniformly, reducing the risk of partial solidification and incomplete discharge.
The trade-off is infrastructure. The E-Wave requires an electrical supply at the discharge port, which is widely available but worth confirming in advance.
The Steam Heater Pad takes a different approach — circulating hot water or steam through the pad to heat the flexitank gradually from all four sides of the container. It's a gentler, more ambient heating method, and for many standard viscous cargoes, it's entirely sufficient.
The Steam Heater Pad's biggest advantages are simplicity and reusability. Installation is straightforward and compatible with standard port infrastructure worldwide. And unlike the E-Wave, the Steam Heater Pad can be reused up to five times — making it a highly cost-effective option for regular shipments on the same trade lane.
As a general rule: choose the E-Wave if your cargo fully solidifies when cooled, if discharge speed is critical, or if you need precise temperature control. Choose the Steam Heater Pad if your cargo is generally viscous but doesn't fully solidify, if you want a reusable solution, or if electrical infrastructure at destination is limited.
Not sure which applies to your cargo? Sun Flexitanks' technical team — with over 20 years of experience across global bulk liquid trade lanes — can advise on the right configuration based on your specific cargo type, route, and discharge conditions.
Both heater pad options are built to Sun Flexitanks' exacting quality standards and are fully compatible with all Sun Flexitank configurations. The right choice comes down to your cargo, your infrastructure, and how much heating control you need. Get it right, and discharge becomes a non-issue — wherever in the world your container ends up.
Talk to the Sun Flexitanks team about the right solution for your cargo.