Cassette toilets remain the most sustainable choice for motorhomes

With an ever-growing number of innovative toilet systems being introduced to the leisure vehicle market, consumers and OEMs now enjoy a wider choice than ever before.
Thetford has compared sealing toilets and cassette toilets on key factors such as hygiene, emptying flexibility, environmental impact and cost. Here is how the company, a world leader in sanitation systems for recreational vehicles, weighs up the pros and cons of the two systems.

 

 

The idea behind sealing toilets is very intuitive: waste is sealed inside an airtight plastic bag and kept there until it is disposed of. The system requires minimal interaction: users simply need to press a button to start the sealing process, clean the unit and empty the sealed bags once they are full. However, this convenience comes with logistical and environmental considerations. The bags are intended for general waste streams, whose disposal and management can be complicated depending on local infrastructure and regulations. If the bags split open in bins, compactors or landfill sites after disposal, hygiene is put at risk, creating environmental and health hazards, particularly when liquid and solid waste are combined. In addition, the plastic consumption and energy use involved raise valid questions about long-term sustainability.

 

 

In a typical use case – two people using the toilet five times a day for three weeks – this equates to 210 single-use plastic bags.

 

• Running costs (three weeks): around €65.00 (€0.31 per bag)

• Purchase price: typically €1,400–1,500.

 

Cassette toilets are a tried-and-tested, proven solution for those travelling by motorhome and caravan. Waste is collected in a watertight holding tank, treated with a few litres of water and a dose of additive. Thetford additives reduce unpleasant odours and gas build-up, and effectively break down toilet waste to make disposal easier.

 

The cassette toilet’s waste tank is essentially a temporary storage container for toilet waste, which is subsequently emptied into the sewage system to be safely treated. For this reason, toilet additives must be safe for wastewater treatment infrastructure, including sensitive systems such as septic tanks, and all Thetford additives comply with EU laws and regulations to ensure exactly that.

 

The tank is emptied at dedicated service points, widely available across Europe and the UK, or at any toilet connected to a public sewage network or septic tank.

 

Compared with other toilet systems in the recreational vehicle sector, cassette toilets use fewer single-use materials and are designed for circular use. Additives and components, such as the Fresh-up Set and Twusch, promote a more sustainable and mindful way of travelling.

 

 

For the same three-week use case involving two people:

 

• Additive use (three weeks)*: less than one bottle of Aqua Kem® Blue Concentrated (11 doses = around €13.50)

• Water use: around 5% of the typical consumption of a household bathroom

• Purchase price: Thetford C220 Series: €639–679

 

*Under normal conditions, 11 doses of Aqua Kem® Blue Concentrated can last up to 55 days. This comparison, however, is based on intensive use, assuming the tank is emptied every two days.

 

 

As the sanitation market continues to evolve – with the emergence of bag-sealing, separation and hybrid systems – it is essential to assess not only the user experience, but also the entire life cycle of toilet systems.
Dirk Valder, Manager Product Management RV/OEM, explains: “We see a clear trend spreading among certain travellers who choose to camp fully off-grid for extended periods. This group’s hygiene needs are different, which creates demand for alternative sanitation systems suited to their particular lifestyle. We take this trend seriously, and have therefore launched a separation toilet and a dedicated kit to meet the needs of those who love travelling this way.

At the same time, the cassette toilet remains the most widely used option, not least because it is designed to work with existing sewage infrastructure, which continues to represent the most tried-and-tested and reliable waste disposal method.”

 

Thetford is committed to promoting responsible innovation, with solutions that meet both customer needs and environmental responsibilities.