Bus air-conditioning efficiency boost

Scientists at the Pacific Northwest National Laboratory (PNNL) have devised a new approach to air-conditioning that is far more compact and lightweight than traditional equipment while promising to consume 10 to 30 times less energy by effectively removing humidity before cooling.

Licensed to Montana Technologies, the ‘AirJoule’ system uses a unique adsorption-based process that is far more efficient than traditional dehumidifiers, and although this technology holds immense potential for reducing the energy consumption of stationary equipment, Montana Technologies is also focusing on the transportation sector. 

“There’s a huge opportunity in electric vehicles (EVs), especially electric buses,” explained Montana Technologies CEO Matt Jore, who claimed that integrating the new dehumidification tech to electric bus air-conditioners “can extend their driving ranges by up to 75 per cent”.

If true, it could help make electric buses more viable for longer routes and reduce the frequency of recharging, especially in humid climates that work air-conditioners hard.

While many buses around the world currently lack air-conditioning due to its high costs and energy demands, the introduction of systems like AirJoule could change this.

“Cooling humid air causes a huge power draw on an EV battery,” said Jore. “In fact, air-conditioning an electric bus stuck in congested traffic draws more power than propelling it down the road.”

Unlike traditional dehumidifiers, which rely on energy-intensive condensation, AirJoule operates using a twin-chamber design, each containing a highly absorbent desiccant material.

“In one chamber, outside air is passed over the paper-thin film of desiccant, pulling water vapour into the material’s nano-sized pores,” explained Pete McGrail, a laboratory fellow at PNNL who invented the system.

“The heat that is generated from absorbing water vapour is then transferred to the other chamber to help release water previously captured in the pores, minimising energy consumption. This balanced heat transfer allows the AirJoule system to continuously operate at ambient temperature, adding no extra load on an A/C unit.”

Instead of developing its own systems, Montana Technologies plans to sell its components to established HVAC firms, branding it ‘AirJoule Inside’.

This strategic approach is poised to facilitate widespread adoption across multiple vehicle types, enhancing operational ranges while also playing a crucial role in lowering greenhouse gas emissions tied to fossil fuel electricity generation, especially in areas with high cooling and heating demands – ultimately contributing to a more sustainable transportation network.

Yutong’s Gamble: Will Australia’s Buses Go EV?

Global bus and coach manufacturer Yutong, with a 95 per cent market share in China and 10 per cent globally, introduced its advanced Yutong Electric Architecture (YEA) technology to the Australian market at this year’s National Bus & Coach Show in Brisbane.

With full-electric buses currently accounting for just 0.2 per cent of Australia’s fleet, according to The Australia Institute, Yutong sees a significant opportunity to electrify the country’s largely diesel-powered bus network. 

YEA, a groundbreaking EV-specific platform in the commercial vehicle industry, has already proven its global success with its unique integration of software and hardware designed to meet the diverse needs of electric buses. The core of this technology lies in its independently developed ‘C-architecture’ and in-house ‘YOS’ operating system serving as the vehicle’s brain and nervous system.

“This strategic shift from ‘product output’ to ‘technology output’ is driving the advancement of electric commercial vehicles,” explained Yutong Asia-Pacific CEO and vice president of the Asia-Pacific Executive Committee (APC) Kent Chang.

He highlighted the technology’s potential to revolutionise transportation systems across the region, where battery electric models dominate the new energy bus market, accounting for 80 per cent of demand compared to just 20 per cent for hybrid, plug-in hybrid, and hydrogen.

In addition to the YEA technology, Yutong also showcased its E7S micro-circulation battery electric bus in Brisbane, designed for urban feeder routes with room for up to 35 passengers, including a dedicated wheelchair area. It has independent suspension and IP68 and IP6K9K ratings for increased reliability.

Yutong isn’t just bringing its technology to Australia, it is building it. The first E12 pure electric chassis prototype, is built in collaboration with Australian body builder Volgren and assembled in Australia by VDI. In addition, the company’s ‘Global Carbon Free Forest’ initiative pledges to plant a tree for every bus sold. 

With more than 190,000 of its ‘New Energy’ buses already on roads worldwide, Yutong is confident in its ability to electrify Australia’s mostly diesel bus fleet.

The ACT government has already placed an order for 90 E12s and Yutong is hoping to supply buses for the upcoming 2032 Olympic Games in Brisbane.