How to Drastically Reduce Your Carbon Footprint By Switching to a Composting Toilet

How to Drastically Reduce Your Carbon Footprint By Switching to a Composting Toilet

How to Drastically Reduce Your Carbon Footprint By Switching to a Composting Toilet

What is a composting toilet?

A composting toilet is a waterless, odorless toilet that treats human waste by composting. Unlike a flush toilet that uses water to send waste to a septic system or sewer line, a composting toilet breaks down waste through natural biological processes.

There are two main types of composting toilets:

  • Self-contained composting toilets have an enclosed tank or chamber underneath the toilet seat to compost the waste. When the tank is full, you empty it into an external compost system.

  • Central or continuous composting toilets connect to a separate composting unit stored elsewhere in your home or property. Waste travels directly to the external composting chamber through a chute or pipe.

Both types rely on aerobic decomposition. Bacteria, fungi and other microorganisms break down waste into humus, a nutrient-rich soil amendment. Proper moisture, temperature and oxygen levels are needed to compost human waste effectively.

Why switch to a composting toilet?

Switching to a composting toilet can drastically reduce your carbon footprint in these key ways:

Saves fresh water

  • A conventional flush toilet uses 1.6 gallons of water per flush on average.
  • A composting toilet uses no water to process waste.
  • This saves thousands of gallons per year per household.

Reduces sewage pollution

  • Sewage treatment facilities require large energy inputs to treat wastewater.
  • Much of this treated sewage still pollutes waterways with excess nutrients.
  • Composting toilets don’t send human waste to sewers or septic systems.

Avoids methane emissions

  • Waste decomposing anaerobically in septic systems and landfills releases methane, a potent greenhouse gas.
  • Composting waste aerobically avoids methane production.

Enriches soil locally

  • The compost end-product is a nutrient-rich soil amendment.
  • It can be used to fertilize your garden or landscaping plants.
  • This also reduces the need for synthetic fertilizers.

How much can a composting toilet reduce your footprint?

Switching one conventional flush toilet to a waterless composting toilet can reduce your carbon footprint by 0.8 metric tons of CO2e per year according to EPA estimates. This is equivalent to:

  • The greenhouse gas emissions from 185 gallons of gasoline
  • The emissions avoided by recycling 3.3 tons of waste instead of landfilling
  • The carbon sequestered by 1 acre of U.S. forests in one year

For a family of 4 replacing all bathrooms with composting toilets, thereduction would be over 3 metric tons of CO2e per year.

What are the benefits of a composting toilet?

1. Saves thousands of gallons of water annually

Composting toilets conserve fresh water that would be used for flushing. This provides major environmental benefits in drought-prone areas.

2. Reduces utility bills

You’ll save on water, sewer and septic costs by not flushing or releasing waste into sewer/septic systems. Composting toilet users see 20-30% reductions in utility bills.

3. Generates nutrient-rich compost

The resulting compost is a valuable soil amendment that can be used to fertilize non-edible plants in your yard and garden.

4. Works anywhere

Composting toilets work off-grid in cabins and rural areas not connected to utilities. Some models work on boats and RVs as well.

5. Easy to maintain

Maintenance involves emptying the compost tank 1-4 times per year depending on use. No need for a septic tank pump-out.

What should I consider before switching to a composting toilet?

Upfront cost

Composting toilets cost $1000-$2500 installed, 2-3 times more than a basic flush toilet. Factor in long-term water savings.

Space needed

You’ll need space for an external composting unit and storage of the end compost. Self-contained units need emptying room under the bathroom.

Adaptation period

It takes time to get used to a waterless toilet. Use extra bulking material like sawdust at first to absorb excess moisture.

Local regulations

Composting toilets are allowed nationwide, but some areas may require permits. Always check local codes first.

Electricity requirements

Some composting toilet models run on electricity to power fans, heaters and conveyance. Non-electric models are available.


Switching from a conventional flush toilet to a waterless composting toilet offers huge potential for reducing your carbon footprint and utility bills. It takes some planning for installation requirements, daily use and end compost management, but the long-term benefits for freshwater conservation and greenhouse gas reductions make composting toilets a change worth considering. Start exploring your options today!