Cloth vs. Disposable Diapers

Franklin Associates, Ltd., 1992

Multiple factors contribute to determining the preferred diaper. A life-cycle assessment by Franklin Associates, Ltd. compared the diapers through process energy (fuels used to manufacture the diaper), feedstock energy (energy within physical materials) and pollutants. Among cloth diapers, Franklin Associates evaluated the energy used in different laundering techniques: home versus commercially laundered. Though only one diaper is more energy efficient, each has its own environmental advantage.ⁱ Cloth and disposable diapers are used at different rates. Cloth diapers are used an average of 10 times per day. Disposable diapers are used an average of 5 times per day. In a year a child can use anywhere from 3,100 to 3,700 cloth diapers or 1,800 to 2,900 disposable. The difference is caused by cloth diapers' ineffective absorption especially for older children. Often two or three cloth diapers are needed to be equally effective as a disposable. This difference was accounted for when comparing each type of diaper.

Franklin Associates evaluated two different kinds of cloth diapers, distinguishing home and commercially laundered systems. 85% of cloth diapers are washed at home. The remaining 15% are commercially laundered. Significant differences lie between the two. Water volume, washing technique, and also uses per diaper directly impact solid and waterborne waste as well as energy efficiency.

In a year, the net energy used and embodied in disposable diapers is 6,900 MJ for one child.ⁱⁱ 86% comes from feedstock energy, which is primarily petroleum-based. The remaining 1,000 MJ is from packaging and process energy. The net energy used and embodied in cloth diapers is primarily from the laundering process. The total energy of the home laundered diaper is 9,600 MJ. 85%, 8,200 MJ is used in the laundering process. While commercially washed diapers use 8,600 MJ, only 5,600 MJ is due to laundering. Overall, a disposable diaper uses 29% less energy than home laundered systems and 20% less energy than commercially washed diapers.

Figure 1 - Total energy used by each diaper type in one year. Feedstock and process energy includes energy used through cotton growing, material processing and diaper manufacture. It also includes energy used and embodied in bleach and detergent.

Differing energy quantities between home and commercially laundered cloth diapers are due to different disposal rates and different energy efficiencies in the laundering process. A home washed diaper is used 160 to 180 times before being thrown out. Diaper companies, desiring a clean look, toss the diaper after 50 washes. In a year, commercial laundering systems cycle through 71 diapers per child while home laundered system use 20 diapers. This causes increased energy use through laundering in home systems but increases feedstock energy for commercially laundered diapers. Despite a higher reuse rate, because the home laundering system is energy intensive, overall it uses more energy than commercially laundered diapers.

Another difference between home and commercially laundered cloth diapers is the amount of water. Home laundered diapers use 34,000 liters of water for one child per year. Commercially laundered systems use 21,000 liters. Not only do commercially laundered diapers use a third less water through laundering, they also use 30% less energy. Because commercial laundering companies have more efficient washing systems, they use 5,600 MJ a year as opposed to 8,200 MJ. Both of these measures conclude that commercially washed diapers are preferred to home laundered diapers; commercial systems use less water and energy through the laundering process.

Solid waste is another important aspect between diapers. Solid waste is divided into two groups: industrial and post-consumer. The two cloth diapers produce nearly the same amount of industrial and post-consumer solid waste, differing slightly because commercial diapers are thrown out early. Cloth diapers produce 160 kg while disposable diapers produce 260 kg of solid waste.

Figure 2 - Volume of solid waste per year. Industrial Waste includes waste used to produce the diaper such as raw material production and process, manufacture trimmings, and ash from electricity generation. Post consumer waste refers to substances thrown out: the diaper itself, child waste, and packaging.

Another measure of solid waste is by volume. It is a much more relevant measurement as landfills are filled by volume, not necessarily by mass. As expected, disposable diapers occupy the most landfill space, filling up 0.40 m² per child per year. Home laundered diapers produce 0.24 m². Commercial systems fill 0.21 m². In terms of volume, disposable diapers produce nearly twice as much solid waste as cloth diapers.

Waterborne waste comes from raw material production, irrigation of cotton fields, laundering steps, and sewage treatment.ⁱⁱⁱ Home laundered cloth diapers produce 10.2 kg while commercially laundered produce 9.6 kg. The difference between cloth and disposable diapers is again due to the laundering process. Disposable diapers contribute the least amount, 1.2 kg. The waste from disposable diapers primarily comes from manufacture and fuel related processes. Because of the water usage of cloth diapers, through laundering, sewage and irrigation, cloth diapers produce significantly higher quantities of waterborne waste.

Atmospheric waste is produced in the greatest quantity by home laundered systems.^iv They produce 13.6 kg per child per year while commercially laundered systems produce 7.8 kg. Disposable diapers produce 6.8 kg. Home laundered diapers produce more atmospheric waste because washing diapers at home is energy intensive. The laundering process indirectly increases atmospheric emissions from electricity generation. This increase is so significant that home laundered diapers produce more atmospheric waste through laundering, than exhaust from transporting commercial diapers.

Certainly action can be taken to reduce energy use. Air drying cloth diapers is one example. If this reduces energy used in the laundering process by 37%, it would be preferred even over disposable diapers. Though solid and waterborne waste would be unchanged, atmospheric wastes would decrease with reduced electricity use. This could potentially leave home laundered diapers as the preferred diaper, but one can only speculate.

With current information, when determining the best diaper through an energy analysis, disposable diapers are preferred. However they produce substantially more solid waste. Cloth diapers produce half as much solid waste but use more water volume and produce more waterborne waste. Evaluating the best diaper depends on local conditions. If in a drought, it's best to use disposable diapers. If the area has landfill problems, it's best to use commercially laundered cloth diapers. If there are air pollution problems, resort to disposable diapers. The best diaper ultimately depends on the community's situation.

ⁱ This review leaves out many details of the summarized work. Opinions expressed by ILEA may not be the same as those of the original author(s). Consult the authors' original work for a full treatment of their analysis and perspective. Franklin Associates, Ltd. Energy and Environmental Profile Analysis of Children's Single Use and Cloth Diapers: Revised Report. Kansas: Franklin Associates, LTD., 1992.

ⁱⁱ ILEA reports most energy values in megajoules (MJ). A megajoule is enough energy to bring about 3 quarts of room temperature water to boiling, or to run a 1500 watt hair dryer for 11 minutes.

ⁱⁱⁱ Waterborne waste accounts for compounds which disturb ecosystems such as dissolved solids, suspended solids, biological oxygen demand, chemical oxygen demand and phosphates.

^iv Atmospheric waste causes smog and acid rain. For diapers atmospheric waste is primarily particulates, hydrocarbons, sulfur oxides, nitrogen oxides and carbon monoxide.

Last Modified on October 1, 2004.