Cleantech Market Intelligence
More EVs Might Mean Changes to Parking Garages
The adoption of electric vehicles (EVs) seems to be unstoppable. In Electric Vehicle Market Forecasts, Navigant Research estimates that plug-in EVs will make up 2.4% of total worldwide light duty vehicle sales by 2023. EVs will thus have a profound impact on the electrical grid, but how will they affect buildings?
Currently, the most visible impact has been the proliferation of electric vehicle charging stations. Driven largely by LEED requirements and state-level incentives, many commercial buildings have dedicated parking spaces for EVs. Indeed, in some markets, EVs have enough of a presence that commercial buildings are installing charging stations in response to demand from the market. But, increased adoption of EVs may necessitate new paradigms for the design of parking garages.
The Solution to Pollution Is Dilution
Parking garages need ventilation. In addition to the carbon dioxide that contributes to climate change, internal combustion engines also emit a lot of other pollutants that are terrible to breathe. Parking garages need to exhaust these pollutants and replace them with fresh air in order to be compatible with human life. Building codes dictate the amount of air that needs to be exhausted based on the worst-case scenario: if every car in the garage was running at the same time.
This approach made sense when sensors and controls were expensive and difficult to use. However, with the sophistication of modern systems, demand-controlled ventilation (DCV) is becoming an attractive alternative to reduce energy consumption. DCV uses sensors to monitor air conditions and match the delivery of ventilated air with the actual need of the space. DCV saves substantial energy because the airflow that a fan provides has a cubic relationship with the power needed. As a result, halving the airflow of a fan reduces the power consumption to one-eighth of the full airflow. Some systems can reduce peak kilowatt-hour demand by up to 95%.
Unlike internal combustion engine vehicles, EVs do not create emissions that need to be exhausted (that happens at the power plant). So, in a future with all EVs, garage ventilation requirements can be drastically reduced. But, in the meantime, the presence of EVs in parking garages translates to greater savings through DCV operation.