The Difference Between Reverse Osmosis and Distilled Water
Understanding these fundamental differences in the scientific and chemical processes of reverse osmosis and distillation helps to appreciate why reverse osmosis is often favored for household water purification. Its efficiency, effectiveness in removing a broad spectrum of contaminants, and relative energy efficiency make it a practical and popular choice for many homes.
- Contaminant Removal:
- Both methods are effective at removing up to 99.9% of total dissolved solids (TDS) from water, but their efficacy in removing specific contaminants varies. RO systems may struggle with certain VOCs, chemicals, pesticides, herbicides, and fungicides, while distilled water might contain traces of chemicals, metals, and particles with high vapor pressure like mercury.
- Energy and Time Efficiency:
- RO Systems: Provide near-instant access to purified water, powered by water pressure or an electric pump.
- Distilled Water: Takes significantly longer to produce, typically 5-6 hours for a single gallon, making it less convenient for instant access.
- RO Systems: Generally more expensive upfront, ranging from $550 to $1,000 or more, with additional costs for filter changes every 6-24 months.
- Distilled Water Systems: Have a lower upfront cost (around $200-$650) but also incur ongoing costs, including electricity and optional carbon post-filters.
- Wastewater Generation:
- RO Systems: Produce wastewater, with some water wasted during the purification process (1-4 gallons of wastewater per gallon of purified water).
- Distilled Water: Does not generate wastewater but consumes more energy due to the boiling process.
Why Reverse Osmosis Systems Are Preferable for Households
- Efficiency and Convenience: RO systems provide quick and continuous access to purified water, making them more convenient for regular household use, especially when immediate access to clean water is needed.
- Removal of Contaminants: Capable of removing a wide range of contaminants, RO systems are highly effective in ensuring safe drinking water, often exceeding the purification levels of average carbon filters.
- Improved Taste and Odor: By removing contaminants that affect the taste and smell of water, RO systems offer better-quality, better-tasting water, which is preferred for drinking and cooking.
- Low Maintenance: Once installed, RO systems require minimal maintenance, mainly involving periodic filter changes. Some systems consolidate filtration stages into fewer filters, further reducing maintenance efforts.
- Variety and Adaptability: A wide range of RO system types are available, including under-sink, whole-house, and countertop units, each with unique features to suit different needs and preferences.
- Health and Hydration: The availability of good-tasting water from RO systems encourages higher water consumption, contributing to better hydration and overall health.
- Cost-Effectiveness: Over time, RO systems are more economical compared to buying bottled water, offering high-quality water at a fraction of the cost per gallon.
- Better Cooking Quality: Using RO water in cooking can enhance the flavor of food by eliminating the taste of chemicals, metals, and other impurities commonly found in tap water.
- Environmental Impact: While RO systems do generate wastewater, newer models are more efficient, and the overall reduction in bottled water usage contributes positively to environmental conservation.
While both reverse osmosis and distilled water systems are effective in purifying water, reverse osmosis systems offer several advantages that make them a more suitable choice for the average household. Their efficiency, convenience, range of options, low maintenance, and cost-effectiveness, combined with the added health benefits and environmental considerations, make them a preferable choice for ensuring safe and high-quality water at home.