High Efficiency (washing machines)
"High Efficiency", or "HE" for short, is a term now being used by the Soap and Detergent Association (SDA). The term refers both to newer washing machines, which apparently use components more sensitive to damage by detergent suds, and to detergents (and possibly non-detergent soaps, though their site seems to avoid admitting that one can use anything but detergent for doing laundry in a washing machine) which are suitable for use with those machines.
Machines labeled using the "HE" logo often require the use of HE-compliant detergents; the use of non-compliant detergents voids the warranty.
It appears that SDA owns the HE logo and is responsible, in some way, for certifying laundry soaps and detergents as "HE-compliant" and allowing their manufacturers to use the logo on their products. This is significant because the use of non-HE-compliant cleaning supplies apparently voids the warranties of HE washing machines. The claim on SDA's web site is that HE washers are highly-tuned machines and need careful formulation of cleaning supplies in order to be able to perform at their best; reading between the lines, the main requirement for cleaning formulas seems to be that they must be "low suds" so that no suds can get into the machinery. There may be other "optimizations", but nothing specific is stated.
Furthermore, it's not clear exactly how a manufacturer of a laundry cleaning supply would obtain "HE compliance", especially whether or not there is a fee involved.
For example: we (The Hypertwins) use a low-sudsing, no-chemical-residue organic soap powder made by Ecover. This powder does not, however, appear to be HE-compliant. The question then is, why is it not compliant? Is there some other requirement beyond "low-sudsing", and if so what is it? Or is it simply a matter that SDA has set up their compliance certification process such that a niche brand like Ecover can't economically afford it? (See 2006-03-14 webmail to Ecover)