South Miami officials say there is one driving factor behind new legislation that requires new construction to have rooftop solar panel systems.

Climate change.

After President Trump announced he was pulling the U.S. out of the Paris Climate Accord, Mayor Philip Stoddard was left wondering what he could do for his city, which is threatened by rising sea levels.

“We have 365 mayors (who have pledged to uphold the accord) who are scratching their heads thinking ‘What can we do,’” Stoddard said. “One thing we do regulate is construction in our own municipalities.”

South Miami officials passed the new law, which will take effect in mid-September, to do their part in reducing CO2 emissions — a greenhouse gas that contributes to climate change — and help slow sea level rise.

The legislation requires new real estate and large additions to be topped by solar panels.

The law is hardly original; it’s modeled after one adopted in San Francisco in 2016.

A June study from the United States Conference of Mayors found that, of the 66 responding cities, 90% were willing to work with other cities to lessen the effects of climate change. About half of the cities already offered incentives to residents and businesses making their homes energy efficient.

The Paris Climate Accord is a landmark agreement to reduce greenhouse gases originally signed by 195 countries, including North Korea. Though it was a hallmark achievement of Barack Obama's presidency, Trump announced on June 1 the United States was walking away from the historic agreement.

The United States is the second highest emitter of greenhouse gasses like CO2. About 97% of scientists say we are already seeing the affects of climate change.

The Conference of Mayors has spoken out against Trump's withdrawal from the Paris Climate Accord before, insisting they will continue to follow the agreement's guidelines.

“The nation’s mayors have never waited on Washington to act, and have been strong proponents of action on climate for decades,” US Conference of Mayors CEO and Executive Director Tom Cochran said in a statement. “Mayors will continue to harness their collective power to continue to lead the nation on this critical issue, regardless of what happens at the national level.”

Mayors aren't the only ones taking a stand against the withdrawal. Also in June, 11 states and Puerto Rico banded together to form the United States Climate Alliance, with a goal to reduce emissions by 26-28% of 2005 numbers. Member states account for about a third of the U.S. population.

Stoddard said he hopes his city helps set example for other governments, like San Francisco did for him. Not only will solar panels help the world on the climate frontier, but it could also prove a good investment for constituents, he added.

“The prices of solar has come down even to the point with the subsidies, you about break even,” Stoddard said.



So, what's the real cost of solar panels?

Though the costs of panel installation have fallen by 70% since 2010, according to research from national solar trade association Solar Energy Industries Association, it takes time for solar panel systems to make money or even break even.

Rooftop solar panels installed in the first half of 2017 will take, on average, more than seven years to pay off, EnergySage CEO Vikram Aggarwal said. Some of those systems will take almost 10 years, he added.

Solar panel systems tend to cost between $12,000 and $16,200, Aggarwal said, adding that price is often after the large tax credits offered by both state governments and the federal government. Currently, the federal government offers a 30% tax credit to purchasers of home systems.

"That price is 13 percent lower than it was a year ago, and solar panel system costs are continuing to fall," Aggarwal said.

In 2015, the average Florida home consumed 1,141 kilowatt-hours — the unit used to measure electricity on a bill — per month, according to data from the U.S. Energy Information Administration, a government entity tasked with collecting information on energy. That spelled out an average monthly bill of about $132, according to the EIA.

In an sunny area, a 6 kilowatt system, which is the average system size in the U.S. Aggarwal said, will produce anywhere from 17 to 27 kilowatt-hours per day on average. Even if a system is producing 27 kWh on a daily basis, it would still fall short of covering an entire electric bill in Florida; homeowners would be left with about a $40 electric bill per month.

Those numbers aren't universal. The average electricity consumption varies widely from state to state and billing rates are different depending on electricity providers.

Solar panels themselves aren’t the expensive part of the process, according to research from the Solar Energy Industries Association, it’s the soft costs, which include engineering, labor and installation.

The Department of Energy SunShot program is working to lower soft costs for homeowners and businesses looking to go green, SunShot’s soft costs program manager Elaine Ulrich said.

Last month, the U.S. Department of Energy announced it was awarding $46.2 million for dozens of projects as part of its SunShot Initiative, which is trying to lower the cost of solar for consumers. EnergySage, a for-profit online solar marketplace, was among the recipients.

A large part of SunShot is working with local governments to make installing solar easier and cheaper for residents.

“In many towns, if you walk into a permit office and say I’d like to get a construction or electrical permit to install solar on my house, they’ll say, ‘We don’t have that permit,’” Ulrich said. “Some of the things we’ve done is help take the permit that other jurisdictions have established and some info on how to put in place a good permit process, and people can adopt those.”

Other ways to keep the cost of solar low can include comparison shopping, purchase systems instead of leasing and take advantage of tax incentives, Aggarwal said.

If cities require solar panels, what are the benefits

Besides helping curve green house gas emissions, there are many short term benefits of installing solar panels.

Ulrich said homeowners often see immediate savings after installing systems.

"There has been research that solar is cost competitive in most of the large cities in the U.S.," Ulrich said.

Solar is often a smart long term investment, she said, adding that the value of solar doesn't depreciates like the value of a home or car would.

Stoddard, whose home is powered by solar energy, maintains purchasing solar panels are one of the best investments a homeowner can make.

“If you don’t have solar on your roof and you don’t have solar, you’re leaving money on the table,” he said. “It’s paying you money. There’s not many great deals in this world like this.”

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