EDR can provide compelling cost advantages in some situations. Unlike RO, which relies on pressurized water, EDR uses voltage differences to drive ions. This results in greater tolerance to inorganic scaling and biological fouling and reduces pre-treatment and chemical needs. The decision to use EDR, RO, or other technologies depends on case-specific conditions, such as feed and product water TDS and if selective ion removal is required. Typical applications in brine concentration, brackish water desalination of groundwater, and ultrapure water production.