Here's my 2 cent rant on what they might want to try.
If you have a piece of technology that works, but sales are not happening, it could be
because of the upfront costs involved? Having functional units sit non-operation seems a waste.
Call up some large companies with fleets of diesel machinery (trucks, diggers, etc.)
Think mining, etc. - companies which consume large amounts of diesel and run often 24/7.
And offer to outfit there entire fleet for ZERO upfront. This may get your feet in the door!
However - what you do negociate - for compensation for installing and mainting these units for
such customer, they pay the company a percentage of fuel savings. I would imagine larger companies with tons of vehicles, etc. must have massive fuel bills, so even if you can scratch out a deal where you get paid a few percent of that total amount, it would be revenue, units in service, exposure, and a press release worthy accomplishment.