Last week, the YouSolar team returned from the RE+ tradeshow in Las Vegas. With a weekend to relax, recover, and reflect, we are ready to report on what we saw at the country’s largest renewable energy trade show.

The show featured lavish booths of the solar panel and battery companies dominating the market.

The vast majority of vendors offer products that rely on the grid and connect using alternating current (“AC’).

For decades, academics and true believers have made the case that appliances should run on direct current (“DC”) and not AC. But there was no compelling reason to switch a house from AC to DC. With current popular systems connecting solar and batteries with AC and tying it to utility power, even solar panels and batteries that run intrinsically on DC have provided no driver for a transition. But all this is about to change!

The next big thing will be appliances moving to direct current (“DC”). And YouSolar is ready.

TRANE converted one of its production heat pumps from AC to DC input and displayed it at RE+. When running on DC, the heat pump is 5% more efficient. The DC version also has simpler power electronics.

Since its inception, YouSolar has built the PowerBloc on a 380 V DC, the emerging standard for DC appliances.

The PowerBloc is a purebred DC system. Yes, we convert power in the last and final step to AC to power today’s homes, but the PowerBloc can also directly power DC appliances.

The transition to DC is already happening. And it starts with DC fast charging at the home or business. While Level 2 charging is limited to about 10 kW, DC-DC charging at the home or office can deliver 20 or 30 kW of power.

The next appliances to convert to DC power will be heat pumps. Trane, one of the biggest manufacturers of air conditioners and heat pumps, exhibited a heat pump that Trane had converted to DC. They loved the results of their tests.

When running the heat pump on DC, it is 5% more efficient. It also has fewer parts.

And with the PowerBloc, the Trane heat pump can run directly on the 380 V DC bus – no inverter required.