Cincinnati Zoo parking lot.
As Berkeley Lab scientists (and others)
point out:
The benefits of cool pavements extend beyond just cooling the local ambient air. They can also impact global warming and energy loads. Dark roofs and dark pavements both contribute to global warming by absorbing large amounts of solar energy stored in sunlight, then radiating the energy back into the atmosphere in the form of heat. Gilbert added: “Across an entire city, small changes in air temperature could be a huge benefit as it can slow the formation of smog. Just a couple of degrees can also reduce peak power demand, by reducing the energy load from air-conditioning.”
Additionally more reflective parking lots could allow building owners and cities to save on energy needed to illuminate streets and parking lots. “Chicago has reported energy savings from using solar-reflective pavements in its alleys,” said Gilbert. “Quantifying that would be something a business, such as Walmart, could literally take to the bank.”
Using something like
solar carports (seen above) could help even more.
It’s just what it sounds like — covering up a parking lot with solar panels, which are elevated above the ground so that cars park in the shade beneath a canopy of photovoltaics. Depending of course on the size of the array, you can generate a lot of power. For instance, one vast solar carport installation at Rutgers University is 28 acres in size and produces 8 megawatts of power, or about enough energy to power 1,000 homes.
Solar carports have many benefits, ranging from aesthetics (yes, the things look very cool) to subtler factors. Like this: Not having to return to a hot car after spending three hours at the mall or a sporting event in the summer. In fact, according to the Environmental Protection Agency and Department of Energy, being able to park in the shade in the summer is actually a substantial contributor to increased vehicle fuel efficiency, because it saves having to cool your car back up by cranking the air conditioner.
The issue, as always, is cost.
“It’s the most expensive type of system to build,” says Chase Weir of TruSolar, which rates solar projects based on financial riskiness. “A lot more engineering, a whole lot more steel, more labor, and therefore, it’s a relatively small percentage [of solar power]…but it is growing, and the cost to install a solar canopy today is less than the cost to install a rooftop just a few years ago.”
However, the cost issues can end up being negated
by state financial incentives:
The solar carport market has become an increasingly substantial sector within the non-residential solar market and the United States solar industry as a whole, growing to 157 MW in 2013. 2014 is expected to be the fourth consecutive year during which greater than 100 MW of solar carport installations were installed. Historically seen as a niche market, recent growth is attributed to falling system prices as well as a shift in the value proposition of solar carports themselves towards educational, government, and non-profit customers aiming for targeted savings on electricity bills. Developers have used this tactic and have exploited state-level incentives to grow the market at a CAGR of 45% from 2010 to 2014.
Solar power is one part of our future. If we are going to incentivize new, innovative businesses, let's make it something worth all of our whiles.