Written by Lisa Walsh

Developer’s Success Story – A Solar Integrated Green Roof in NE DC

By Lisa Walsh | Commercial Solar Developer | Solar Energy Services, Inc.

For the newly-finished Taylor Street Storage facility in North East DC, a 17,500 square foot green roof with fully integrated solar panel array that showcase a value-stacked, elegant design providing both a cost-effective solution to storm-water management. All without forfeiting the solar panels that generate income via federal tax incentives and DC’s superb solar production-based financial incentives.


With over three million square feet of green roofs in Washington DC and 50MW+ of solar installations – the City is no stranger to either technology. However, the integration of both on the same roof is less common, despite the symbiotic relationship between the two offering a number of advantages.


Beds of Sedums awaiting Fall planting at Taylor Street Storage, Oct 2018.
Photo Credit – David Gorman of Lock 7 Development

Completed 133.980kW Solar-Integrated Green Roof at Taylor St NE WDC
Photo Credit – David Gorman of Lock 7 Development

Storm-water Management


Approval for a commercial building permit in Washington DC must include a storm-water management plan as defined by DC’s Department of Energy and the Environment (DOEE). For Taylor St, the Development team could have chosen between:

  1. Lost parking spaces to house costly underground containers for capturing and storing runoff
  2. Payment of ever-increasing storm-water management fees
  3. Implementation of a multi-layered Green Roof to treat 100% of the rainfall obligation with a perennial, sedum based plant surface – as per DOEE requirements.
    The green roof offered a cost-effective storm-water management solution that required no additions or demo’s to the existing structure.
    Solar Panels

Solar Panels

Most savvy developers realize that an empty roof in Washington DC is money left on the table. With the best solar financial incentives in the USA, the payback is rapid followed by years of production-based paydays. Small wonder that the development team at Taylor Street were interested if – and how – a solar array could integrate with a Green Roof. The good news is not only does the solar system seamlessly integrate with the green roof but the relationship is one of symbiosis and cost-effectiveness. Here’s why:

BALLAST. Most solar systems installed on DC’s commercial flat roof areas are ballasted. i.e. an assortment of concrete blocks, along with the weight of the solar panels and racking, is engineered to hold down the weight of the array with minimal or no penetrations to the roof membrane.
With close to 35 PSF of weight, a green roof more-than provides this ballast negating the need for concrete blocks or supplemental attachments. This is worth mentioning as the Green Roof is now a fully engineered component of the solar system bringing the question of tax credit eligibility into play. Is the Green Roof, or portion of, now eligible for the 30% Federal Tax Credit? Certainly worth conferring with a tax adviser.

A close up of the Solar System mounted into the soil on the roof.

CREATION OF A MICRO-CLIMATE: Furbish designs their perennially healthy green roofs with a wide palette of sedum species. These drought-resistant succulants require little maintenance and have varying requirements for daily sunlight – from full-sun to all-shade. Contrary to first impressions the intermittent shading and weather protection provided by the solar panels provide a micro-climate highly conducive to the plants underneath, in between and around the solar arrays.

DESIGN: Most ballasted solar systems have ample aisles between each row of solar panels insuring that each solar panel is optimized and avoiding shading from the panel row in front. Solar panels can also be tilted anywhere between 5 and 35 degrees. This is adjusted to account for shading, panel count and orientation considerations. This flexibility of design was helpful for integration the green roof. Aisle spacing, solar panel size and tilt were designed with the Green roof in mind – not only as it relates to healthy plants, but also for annual maintenance access requirements.

Established Example featuring similar product and design as Taylor Street


CHALLENGES: Solar-integrated green roofs are not as common as their singular counterparts. Fair to say this project did not come without some challenges


DOEE DESIGN STANDARDS: Department of Energy and Environment is responsible for DC’s Stormwater Management and insuring all DC buildings comply with runoff standards. The burden was on SES and Furbish to ensure that the solar arrays were not going to impede the ability of the plants to thrive and provide the necessary water retention requirements. The design and permitting side of the project insofar as panel tilt, aisle spacing and racking integration were designed in collaboration with DOEE.


INSTALLATION TIMELINES: Furbish Company are Green Roof specialist, Solar Energy Services, Inc. are solar specialists. Integrating these technologies took heightened coordination between our installation teams, mostly in terms of labor efficiency, communication and timeliness. The latter was particularly stringent as the Certificate of Occupancy, required to meet the developer’s lease requirements, was contingent upon the completion of the Green Roof which now included solar racking, wiring and panel installations. Throw in some PEPCO Permission to Install challenges related to the solar portion, and the pressure was on.


The project came with some unusual PEPCO interconnection timing challenges at the end. Ironically not related to the Green Roof aspect of the application. Nonetheless, this system is now outputting electricity like gangbusters. All’s well that’s ends well.

Written by Rick Peters

Maryland Solar – Ready to Grow Again

For many years, Maryland has been a leader in solar policy and solar deployment.  In the last 3 years, we’ve fallen behind other states, watching our robust growth give way to several years of decline.  It’s almost hard to believe, but Maryland has been losing solar jobs for more than two years after peaking at approximately 5300 in late 2016.

Policy Clouds

Why is this happening?  One of the biggest reasons is the value of the state solar production incentive, the SREC (Solar Renewable Energy Certificate).  Those of you who own solar or have considered buying solar are probably all too familiar with SREC pricing.  Because Maryland property owners adopted so much solar in the first half of the decade, we outpaced the state’s goals, depressing the value of the market-based SREC incentive.  This was a good problem for the industry to have until it became clear that our goal (25% renewables by 2025 with 2.5% solar by 2022) was clearly not aggressive enough.

The Time is Now

We are now at a time of severe urgency for the Maryland solar industry.  With installations on the decline for over two years and job losses mounting, we are losing a trained employment base and leaving federal tax benefits on the table.   The solar industry has been working with other coalition members (wind industry, environmental organizations, etc.) for a few years to try to increase the state’s Renewable Portfolio Standard (RPS), but have been hampered by the Hogan Administration’s reluctance to incentivize more renewables until the completed RPS Study Report is released.  The study was due to be released in December of 2018, but has been delayed and some fear this is intended to stall an RPS increase for another year.  We cannot wait.

Governor Hogan has gone on record with his desire to fight climate change.  He recently coauthored an OpEd in the Washington Post with Virginia’s Democratic Governor, Ralph Northam to emphasize the urgency and the need for bipartisan solutions to climate change.  It is in this bipartisan spirit that we hope to see the Hogan Administration support the Maryland General Assembly in passing the Clean Energy Jobs Act
(CEJA)(SB0516, HB1158) of 2019 that will increase our renewable energy goal to 50% and the solar portion to 14.7 %. “Click here to read more about this

No-Brainer Investment for Maryland

One of the primary arguments against increasing the RPS has to do with the impact on utility ratepayers.  The preliminary indication is that the increased renewable goals associated with the CEJA will add approximately $1.85/mo. to the average electricity bill.  While this is not insignificant, it is important to note that a 2018 Daymark study, commissioned by the Hogan Administration’s Public Service Commission, found that for every $1.00 of investment in solar, we return approximately $5.00 in economic and health benefits to the state.   Solar jobs are good jobs that pay well, representing a path to economic stability for many installers.  And best of all, solar installation jobs cannot be exported.

We need YOUR help

As a solar advocate, we ask that you commit to express your support for CEJA in the Maryland legislative session this year.  The bill has been submitted and we should have a bill number shortly.  In the meantime, please continue to advocate for more solar whenever you can and be prepared to contact your Maryland state legislators to support this important legislation when the time comes.  Stay tuned for a special email notification with the bill number, and suggested talking points in the coming weeks.

Written by Rick Peters

Solar is Booming in Washington DC

Washington DC has been a leader in solar development for many years.  In the last 12 years, DC legislators have set aggressive targets, helped to streamline solar permitting, introduced a solar access rights law, and passed a landmark community solar bill to increase access to solar for those without an available sunny rooftop.   Many of these policies include mechanisms to help bring the benefits of solar to communities of low and moderate income.  The collaboration between the solar industry and DC policymakers has helped to build a robust market where solar installations are happening throughout the city, from downtown office buildings to churches, warehouses and residential rooftops across the city.   These policies and the resulting private investments are creating good jobs in the District and reduced energy costs for many of its residents.

Double Down

Since solar and clean energy have been delivering in DC, the stakeholders decided they wanted a more ambitious goal.  In the summer of 2018 the District started on a path to double down with their commitment to renewable energy by proposing the most aggressive renewable energy target in the country when compared to other state policies.  The new goal calls for 100% clean energy (5.5% solar) by the year 2032, with 10% solar by 2041.  Hawaii and California are the only other states that have 100% goals, but both of those targets are positioned for 2045, quite a few years later than DC. 

Other Benefits of the legislation

In addition to doubling the renewable energy target, the proposed legislation would provide a few more benefits to solar advocates.  The bill:

  1. Limits geographic eligibility over time to concentrate the solar development in the District or on the District’s grid
  2. Pulls the current solar carve-out schedule forward by two years to increase SREC demand
  3. Extends the solar carve-out from 5.5% in 2032 to 10% by 2041
  4. Addresses specifics about previously contracted (“grandfathered”) load that is exempted from the newest RPS
  5. Includes transparency requirements on the energy suppliers to provide insight into the exempted load and associated time periods
  6. Modifies Alternative Compliance Payment (ACP) schedules to require $300 ACPs through 2041
  7. Increases the shelf-life of an SREC from three to five years, increasing SREC price liquidity and stability.
  8. Introduces various reporting requirements on the Public Service Commission in order to keep the Council and the Public apprised of the progress of renewable energy development.

We’re in the Home Stretch

The Clean Energy DC Omnibus Amendment Act of 2018 was introduced in July 2018 and made its way through the Council over the fall with hearings and two unanimous votes of support on November 27th and December 18th.  In January, the bill was submitted to Mayor Bowser for her signature and she obliged on January 18thClick here to read the bill“.   The remaining hurdle is for approval by the US Congress within 30 legislative days.  The only way that Congress can stop this legislation is with a joint resolution and the President’s signature.  As a result, passage into law is considered by most to be inevitable and in fact we are seeing market pricing for SRECs responding accordingly.

Thank your Legislators

So now that the law is almost passed, it is time to prepare to deliver.  The industry has a lot of solar to build and we’re working hard at that.  As a solar advocate who cares about renewable energy in DC, please consider taking a few moments to call or write to your Councilmember to thank them for their support of Clean Energy DC Omnibus Amendment Act of 2018.  It’s always important to show our gratitude.

Thank you for your support of solar!

Written by John Marrah III

Buy American and Save

For the month of February SES is offering $1000 off of any solar system that includes US Manufactured Panels.  That’s right, support US manufacturing and Save!  All you have to do is reference this offer during or before your site visit.

Here’s 5 More Reasons Why:

1.    Provides Jobs

The Solar Industry’s growth and inherent job creation is no secret, we are leading the pack among every other industry nationwide. Most of these jobs are being created on the installation side, but we also need to support the rest of the value chain.

2.    American Independence Includes Energy Independence

We as Americans have pride in our nation and in our independence. By generating our energy locally, with renewable resources, and US products, we strengthen our country and our independence, both individually and collectively as Americans.

3.    Do It for The Environment

Current technologies allow manufacturers in the US to support a greener, cleaner solar manufacturing process. If we invest in American-made products, we strengthen our manufacturing base, support US jobs, while insuring  that we are doing our part to contribute to a cleaner environment for ourselves, and the generations to come. Also, by reducing the need to ship overseas, the net carbon footprint is much lower

4.    We Control Labor Standards, They Don’t

The US is a leader in fair labor and safety standards. With minimum wage and safety regulations in the workplace being upheld, you can be sure that your panels are made by people who are being supported and treated fairly in the workplace.

5.    Guaranteed Quality of Goods

The term “Made in the USA” speaks of quality, excellent craftsmanship and a superior product. With a lower cost of labor abroad, many factories rely on fabrication and assembly processes by hand. This introduces higher rates of  failure when compared to the American Standard of automated soldering and assembly. While panel quality continues to improve in the aggregate, US products remain the leaders in quality and performance.  Price tags are slightly higher for Made in USA products, but you find true value among longevity and performance.

Written by Anonymous

Baltimore Business Thermal SRECs

Maryland Solar Water Heating Bill Moves Forward

The House of Delegates voted 132-5 Saturday, following the Senate’s unanimous 47-0 vote March 17.

The legislation would allow owners of solar water-heating systems to sell renewable energy credits. The credits are bought by utilities and power companies that need to meet government quotas of renewable energy generation; if they can’t generate enough green power on their own, they can buy credits from someone else who has.

The ability to generate credits via solar water heating makes those systems a more attractive investment and rewards the buyers for using less fossil fuel. That is expected to be a boon for the green power industry, seen as a growing source of new jobs.

Gov. Martin O’Malley pitched the legislation along with dozens of lawmakers as co-sponsors. House and Senate versions of the bill still must be passed by the opposite chamber, which is expected since the two bills are identical. O’Malley is then expected to sign off.

Written by Rick Peters

SES Letter to The Capital

Your recent editorial (The Capital, April 18) suggested Gov. O’Malley should put more emphasis on the distributed approach to renewable energy, where solar and wind power are generated by smaller systems throughout the state. In fact, the governor intends to sign legislation next month to do just that. Delegate Sally Jameson and state Senator Robert Garagiola sponsored what is essentially budget-neutral legislation (HB/933/SB717) to open up the state’s solar goals to include solar water heating, a very mature and efficient technology, first patented in Baltimore in 1891.

This family friendly technology currently saves a typical family of four about $500 per year on electric bills by obtaining 75 percent of their annual water heating energy from solar. The new law will allow system owners to sell green credits to help utilities comply with the state’s solar goals. Consequently, homeowners will now see simple paybacks on these affordable systems shortened from five to eight years to a very manageable two to four years, on a 25-year lifespan.

Aside from advancing our solar goals, and allowing modest-income homeowners to participate in the benefits of solar, there are significant economic benefits too. Solar water heating is a labor intensive installation, which keeps dollars recirculating in the community. It requires trades people to install it, a group much in need of work.

The components are low tech, but heavy and bulky , so there is strong incentives to manufacture domestically, if not locally. A typical residential system only requires 40 to 80 square feet of sunny roof, drastically increasing the potential pool of participants.

As a daily consumer of solar-heated water himself, O’Malley is well aware of the opportunity for Maryland. I commend him and our legislators for their leadership on this issue.