HVAC and the road to net-zero buildings

aerial shot of Carrington View, a net-zero ready building in British Columbia, Canada

photo by Copper Sky Productions

British Columbia wants all new construction to be net-zero energy ready by 2032. To incentivize companies to invest in this goal, the provincial government enacted the BC Energy Step Code as a regulation in April 2017 and, finally, a legal force in December of the same year. For commercial buildings, the Step Code consists of four steps, each indicating a higher degree of energy efficiency. The fourth step – the highest – is reserved for buildings that are net-zero ready.

This drive toward net-zero buildings is in line with the principles of real estate developer Highstreet - and they wanted to lead the way. The Kelowna, BC-based company was determined to prove that sustainable development is not only achievable, but can be done for no additional cost to the consumer, today.

As the team began its low-impact design on the high-efficiency building that would be known as Carrington View Building A, they had their sights on step four - the highest standards of the BC Energy Step Code. Achieving this would make Carrington View Highstreet’s first net-zero energy ready building, more than a decade before it becomes the standard across the province, setting the bar for all future Highstreet projects.

“This is the direction we’re heading in for every building afterwards,” said Anna Schneider, Marketing Manager for Highstreet. “We’re hitting Step Code 4 twelve years before it becomes the regulation across the province. We’re trying to make that the industry standard, and we want to be at the top of that.”

Challenges

When it comes to low-impact design and high-efficiency building, Highstreet aims to be an industry leader. As they began working on the design and development of their Carrington View project, they scrutinized every detail of the design to ensure the smallest possible carbon footprint from the new building. Finding efficient heating and cooling solutions were an integral part of meeting these ambitious goals. Ultimately, the aim was to meet the highest level (step four) of the BC Energy Step Code, which aims to have net-zero energy ready buildings a standard by 2032.

Solutions

Panasonic’s WhisperComfort™ ERV Balanced Air Solution was chosen as the ventilation technology that best matched the ambitions of the project. Of its features, three were of particular importance: The WhisperComfort™ offers high effectiveness, low fan power and the ability to control the ventilation rate (the cycle of the unit). Meeting the ASHRAE 62.2 standard for indoor air quality, this ability to time the cycles ensured that the system would not waste energy and over-ventilate the space.

Results

Not only did Carrington Views Building A meet the minimum requirements of step four – it exceeded them. The building is expected to have an annual emissions footprint of 879 kg CO2 per year from energy use, less than the average automobile in North America.

One of the largest CO2 contributors: HVAC

To achieve the goal of making Carrington View Building A net-zero ready, every detail of the sustainable mechanical design - from building materials to operational equipment - was scrutinized in order to achieve the lowest possible carbon footprint while maintaining high thermal comfort. Determining the proper HVAC system was no small detail for a project of this size. According to the Small Business Association, these systems represent roughly 40% of electricity usage in commercial buildings.

To help determine the best ventilation solution that would meet the project's needs - from the perspectives of both a utility and energy consumption - Highstreet examined various technologies along with Reinbold Engineering Group, a consulting firm that joined the project in the early, planning stages. Through this assessment process, both Highstreet and Reinbold determined Panasonic’s WhisperComfort™ ERV Balanced Air Solution was the best match.

Cutting usage

Richard Outtrim, Principal at Reinbold Engineering Group, a firm that specializes in energy conservation, said three features of the WhisperComfort™ ERV were of particular importance: its high effectiveness, low fan power and ability to control the ventilation rate (the cycle of the unit).

“We made this decision very early in the design process,” Outtrim said. “We know one of the biggest barriers to hitting these goals is the heat required to ventilate a building. Energy-recovery ventilators are the best strategy for reducing the energy that is associated with ventilation.”

This ability to control the rate of the unit’s cycle is made possible through its ventilation timer, which meets the ASHRAE 62.2 standard for indoor air quality. It provided the engineers with the ability to ensure they were not wasting energy by over-ventilating the space.

Surpassing the goals

The result is an extremely efficient building that produces fewer carbon emissions in one year than an average North American automobile.

According to statistics shared by Highstreet, this high-performance building is "expected to have an annual emissions footprint of 879 kg CO2 per year from energy use." By comparison, an automobile that travels 20,000 km – a little more than 12,000 miles – generates 4600kg of CO2 from energy use per year.

Even more drastically comparative, "the same building using typical Alberta electricity would have an emissions footprint of 217,479 kg of CO2 equivalents per year, nearly 250 times as much [as Carrington View Building A]," Highstreet shared.

At the onset, the goal was to achieve Step Code 4, the highest level of the BC Energy regulation. These final results surpass the minimal requirements for this level.

"Highstreet is pushing the targets way ahead of the curve and leading the charge in terms of energy efficiency," Outtrim said.