When a tiny new dishwasher was unveiled at the Consumer Electronics Show in 2018, I immediately wanted one for my equally tiny house. The device, called the Tetra, could clean only a couple of place settings at a time, but it took up little space on a countertop, washed the dishes quickly, and didn’t have to be hooked up to plumbing. It also used very little water—far less than I was using to wash dishes by hand in drought-stricken California.

Heatworks, the South Carolina-based company that created the dishwasher (with design work from Frog), initially planned to have it on the market by the end of 2018. Four years later, the company just started taking preorders. That’s largely because as the standard dishwasher was being redesigned, there was the realization that the detergent also needed a redesign.

[Image: courtesy Heatworks]

The company first started working on dishwashers because the appliances can use its core technology, which heats water without electric heating elements. CEO Jerry Callahan was also thinking about dishwashers in his personal life. “My wife and I became empty nesters, and we’ve got this big, full-size Bosch dishwasher that runs once every five days,” he says. “You leave dishes in there, the harder it is to get them clean. I started thinking about how dishwashers waste energy and water. I’m like, there’s got to be a better way to do this.”

A basic dishwasher hasn’t evolved that much since the 20th century, other than stainless-steel fronts, some extra buttons, and improvements in efficiency. Callahan wanted to rethink the size, both for use in small apartments and for households with only a couple of people who don’t need the huge capacity of an ordinary dishwasher.

[Image: courtesy Heatworks]

The team hacked together an early prototype from pieces of larger equipment. They quickly realized that the design wouldn’t be a matter of just shrinking components. “We needed to think of it as a whole new device,” Callahan says. The water flowed differently, for example, than in a regular-size unit. They worked with Frog on a version of the prototype to show at CES, where it won an innovation award (and won another award the following year). People wanted to buy it—the first CES show generated a list of about 25,000 interested customers. But Callahan thought it needed to change in a significant way before it could actually go to market.

The problem: It wouldn’t be easy to use detergent designed for larger machines. “We can’t take this thing to market and have to give a matrix to the customer saying, ‘If you use a pod, you need to cut it in half; or if you use a tablet, you need to cut it by two-thirds.’ ” If a customer dumped in too much detergent, for example, because the machine uses so little water, it wouldn’t rinse well.

[Image: courtesy Heatworks]

As more was learned about detergent, there was the discovery that detergents don’t work perfectly: Different ingredients perform different functions, from prewashing to cleaning to making plates shiny, but when they’re mixed together in a gel or a pod, the chemicals interact to make each other degrade. (“The hack is, when you buy dishwashing detergent, use it as quickly as you can, because it’s going to degrade pretty quickly. . . . If you have some that’s a year old, it’s going to be half as effective as one that’s relatively brand-new,” Callahan says.)

Heatworks partnered with chemical company BASF to design a different system that squirts ingredients separately into the machine at the right time in the cycle. In tests in dishwater detergent labs, they found that the tiny machine cleans dishes 35% better than the best standard dishwasher and detergent. A bonus for the company, of course, is that now you have to buy your detergent directly from them.

[Image: courtesy Heatworks]

The design now also includes space for more dishes—and slightly larger items, like mixing bowls—after feedback from early tests. (It can hold a total of three dinner plates, three bread plates, three glasses, and three sets of silverware, or a combination of other items, like baby bottles. The fastest cycle takes less than 30 minutes.) The change in size meant more mechanical and hydraulic tweaking. The filtering system was also improved, so as you watch it operate through the clear window, the swirling water is always clean. “It’s pretty mesmerizing,” Callahan says. “Everyone who owns a cat should buy one because cats sit there and watch the thing all day long.”

He says that he doesn’t regret the delay in bringing the product to market because it is fundamentally better than it would have been. And it still uses very little water—before you use it, you pour 3 liters in a small tank. If someone uses it once a day instead of washing by hand, the company estimates that the device will save nearly 4,000 gallons of water in a year.