Homes are designated as historic so that their iconic characteristics can be preserved, after all. So at first glance, it may seem like installing solar PV panels on historic homes might alter their appearance — and possibly violate the laws and regulations governing these properties.
That’s not always so, it turns out. PV solar was famously installed on the Vatican back in 2008, and on the White House under Presidents Carter and Obama. It’s possible with other historic residences in U.S., too — as long as the process and end result complies with federal or local laws and regulations, as well as historic preservation guidelines.
The National Alliance for Preservation Commissions (NAPC) and the U.S. Department of the Interior’s National Park Service (NPS) have each set up general guidelines for installing solar systems. And some local jurisdictions, such as Montgomery County in Maryland and the preservation commission in Arlington, Mass., have done so as well.
“The guidance makes an important distinction that the solar installation will not impact the historical character of the house,” said Adam Lenz, an environmental planner for the City of Richmond, Calif. Just a few weeks ago, the city worked with nonprofit solar group Grid Alternatives to install their first solar PV system at a unit in Atchison Village, a historic and cooperatively-managed housing community.
The process — which included a back-and-forth consultation that Lenz facilitated between the housing community’s board of directors, the city’s historical preservation committee, city planners and Grid Alternatives — took six months from the planning to the final installation process.
Still, the journey to solar wasn’t that speedy overall. It took about four years for the housing community’s board to come to consensus that one 1.1-kW system could be installed as a pilot project.
It was imperative that the design of the system had the same slope and angle of the eaves of roof itself, according to Lenz.
That’s in line with both the NAPC and NPS guidelines, which emphasize that the panels should be installed flat and not alter the slope of the roof, the installation of the panels should not replace or damage any historical materials, and that the solar panels can be removed if necessary. Both also state that the visibility of these systems should be limited.
Yet although these guidelines can provide a road map, determining the suitability of solar on historic home is still determined on a case-by-case basis, just as it is with any conventional solar project hinging upon available sun and roof access.
So it isn’t surprising that not all historical preservation commissions have welcomed solar with open arms. In 2012, one Washington, D.C. couple’s quest to install a system on their home was shut down by a small majority of the District’s Historical Preservation Review Board, The Washington Post reported.
As it turns out, the naysayers’ convictions originated from their beliefs that some of the PV panels’ planned locations were prominently visible from the street and had the effect of creating a “visual intrusion” on the house and the street — a decision viewed by some as one that could place limits on residential solar in the future, according to The Washington Post.
And even with a successful installation under its belt, the City of Richmond is still treading softly in its desire to get more solar on the roofs of Atchison Village. Later this spring, Lenz plans to check back in with the residents on the process before moving forward with more installations.
“We’d like to reengage the community there and provide a report out on what happened first,” he said.
Photos courtesy of the National Trust for Historic Preservation.