I completely agree, I get sick when I see that are vacuums that it's wattage is as high as 2500 watts, it's such and unnecesary waste of electricity when a 1000 watts motor can do the same job.
But as Jmurray said, when the fans are bigger, they become more expensive. Also, the vacuum cleaners are much smaller than they used to be years before, so the manufacturers put smaller lightweight motors that could fit its size. The small fans can't move the same amount of air, so that way, the motors needs more energy and of course, that increase in the motor rpm causes overheating, a huge energy consumption and (of course) it made them screamy loud.
Of course the solution is simple, I don't think it would be a problem to make bigger motors and reduce the wattage, the problems are that the market sells the vacuums for their wattage, making people think that if the number of whatts is bigger, they will be more powerful, when it's AIR WATTS/AIR FLOW whats it makes a vacuum cleaner more or less powerful.
In conclusion, if the demand of the consumers are small, cheap, vacuums with high speed motors (and they do sell well), the companies will still produce them, it's everything about marketing.
WOW! I didn't realized how much I've written, I could go on and on talking about it hehe.
Have a grrreat day guys!
Kevin.
