Gonna keep this one short.
Can we do filter papers better please?
Rinsing paper filters is an obscene waste of water and of energy, not to mention being an additional step in the coffee making workflow.
It takes a lot of power to get water up to around 95C. I’ve seen up to 1L of water being advocated as sufficient to rinse a Chemex filter, perhaps twice as much water as will be used in the brew itself. This is the equivalent of driving a Hummer. At current Irish electricity rates and doing 50 chemexes a day, this practice alone would cost an (approximate) additional €300 per annum in energy costs. Probably won’t put anyone out of business, but it’s so unnecessary. Indirectly you can add in the requirement for a greater capacity boiler due to essentially needing 3 times the capacity – so a more expensive boiler to start with, larger boilers tend to lose more heat (larger surface area) as well and add to the energy cost in that way*.
I do, however, like the cup quality from a good paper filtered brew. I like the cleanliness compared to a (typical) metal or plastic filter, I like the lack of clean up and maintenance compared to cloth. It is a convenient, and adequate quality medium.
Filter papers need not require rinsing. The Kantan filter imparts no great papery flavour. Our batch brew filters impart no great papery flavour (perhaps more due to the ratio of paper to coffee rather than the papers themselves). It is not beyond the capabilities of technology to develop a filter paper which can meet this rather modest goal (a chemex paper made from the Kantan material would be nice).
We should do it better. Let’s.
*you can of course somewhat mitigate this by the fact that it also preheats the receptacle, but preheating should not require as much water.