Calling all architects! Help us recover from “Pointy Roof Disease”

Ok, this post is from the perspective of a rooftop solar energy advocate, but hopefully it will spark some serious discussion and eventually design changes!

Let’s take a look at what has become of roof designs of new homes in North Texas. Let’s take a look at solar PV technology. And, let’s take a look at the recent “solar-ready” provision in the optional section of the 2015 International Residential Codes. Ultimately, we need help from architects to develop innovative ways to couple new roof designs with solar-ready features to help North Texans on their path to “net zero” homes.

First, what is “solar-ready”? A new solar-ready home is designed and built to prepare for the most efficient use of solar PV (photovoltaic) energy panels in the future. Homeowners have the choice of installing the panels immediately after construction, or waiting to exercise this option at another time. There are several factors that make a home solar-ready:

• installation of appropriate electrical systems
• adequate south-facing roof space
• angle of the roof to the position of the sun

Specific details are available in Solar Ready Provisions, Appendix U of the 2015 International Residential Codes. Building a solar-ready home saves time and money. It enables a homeowner with an energy efficient home a future path to “Net Zero”. This means its solar PV system generates enough electricity during the year to offset all or nearly all of the home’s electricity consumption for the year.

According to Wikipedia - A roof is part of a building envelope. It is the covering on the uppermost part of a building or shelter which provides protection from animals and weather, notably rain or snow, but also heat, wind and sunlight.

One of the great things about rooftop solar PV is that it can leverage the normally unused space of a home’s roof. It can allow the roof to serve its normal function as described above, and a second valuable function to capture light energy from the sun to help power our home’s electricity needs.

Now here is the rub. For whatever reason when it comes to roof designs, it seems that the one with the most points and angles wins. Over time, it seems a bit like the spreading of “Pointy Roof Disease”. All these angles and all these points, especially when placed on the south facing roof, make it very difficult, if not impossible to have a solar-ready home.

Take a look at the following photos of North Texas roofs. Ask yourself, what is the purpose of the angles/points? What is the function?

Fig 1 – Three main roof surfaces. For a south facing roof surface, having just one main surface would greatly facilitate cleaner installation of solar PV.

Fig 2 – Five (or six) roof surfaces. Reducing this to maybe two surfaces would greatly facilitate cleaner installation of solar PV.

And these that follow seem to be competing to win the prize for the MOST points and angles. If these represent the south facing roof surfaces, then these roof designs virtually eliminate the potential for a productive rooftop solar PV installation.

I wonder - what is the function of this “extra” triangle protrusion on this roof?

And what is the function of this double peak with the trough that would be a great place for roof leaks to form?

So which of these do you think wins the prize for the MOST points and angles? And which one has any chance of installing rooftop solar PV in the future and achieving net zero? Sadly, these roof designs are severely limiting the future potential of net zero homes.

The goal of this blog post is to raise awareness and start a dialog to promote solar-ready home designs! Share it with your friends. Reach out to encourage architects to begin providing creative solutions and tackling the transition to solar-ready home designs. Tell homebuilders that you want to buy homes that are solar-ready! North Texas uses more electricity per residence than any other part of the state. Combining new energy efficient home designs with solar-ready home designs creates a sustainable path to the use of clean local distributed energy and reducing the strain on our electric grid for all of us!

Calling all architects! Help us recover from “Pointy Roof Disease”! Bring on the age of solar-ready homes! Comments welcome and encouraged!

Shine On!

Plano Solar Advocate (LH)

US Energy Policy and Home Ownership

An “Open Letter” to our Texas elected representatives 

to the US Senate and House of Representatives

As a homeowner in Texas, I feel that home ownership and long term investments in our homes, helps to facilitate a strong foundation for families in Texas and the United States.

My family recently made a long term investment in our home by purchasing a solar photovoltaic (PV) electric system to capture the local clean energy falling on our home every day. The US Internal Revenue Code Section 25D residential solar investment tax credit (ITC) is achieving its goal to encourage individuals to increase investments in residential renewable energy systems. It helped our family, and many like ours, to make the personal long term commitment to invest in energy freedom. It is a great feeling to be more energy independent!

Using rooftop (or onsite) solar PV technology now available has the great advantage of generating the electricity where it is consumed. This helps all electricity consumers by reducing the strain on the overall electric grid and reducing energy losses that occur when transmitting electricity over long distances. And especially in Texas, solar PV generates the electricity when we are using it the most – when the sun is shining! (It was especially satisfying to know that when the Texas electric grid was hitting peak demand last week my solar PV system was helping to offset some of this peak electricity demand.) As Texas continues to grow, building more of our new homes with solar PV systems to make them net zero (i.e. they produce as much energy as they consume on an annual basis) will further reduce the strain on our electrical grid and help more citizens to become more energy independent!

The Section 25D residential solar ITC also accelerates growth of small businesses across Texas and the rest of the country - businesses that install, contract, or work on residential systems. A recent policy brief titled “Clean Energy Employment Booming, Creates a More Diverse Workforce and Higher Quality Jobs” indicates that Texas had over a 60% growth in solar jobs in 2014. While the rooftop solar market has grown dramatically in part due to third party ownership and leasing, the residential market is beginning to further expand with loans and direct ownership models making the section 25D residential solar ITC extremely important for years to come. For additional information on solar jobs in Texas, see the 2014 Texas Solar Job Census Report.

If the Section 25D solar ITC does expire at the end of 2016, it will stack the deck against homeowners who wish to make this long term investment in their home.  This is because the similar Section 48A solar ITC for commercial owners, while currently set to step down in percentage at the end of 2016, will not go to zero like the residential solar ITC. Thus commercial owners, including third party owners leasing rooftop solar PV systems to homeowners, will continue to receive a solar ITC. Additionally, commercial owners will continue to receive a business depreciation incentive which is not available to residential homeowners.

While considering the tradeoffs for renewable energy incentives/subsidies, I did some research on the long term history of energy incentives/subsidies in the US.  What I found is that all energy sources have benefitted from long term and continuing government incentives. (For example, see reference The Historical Role of Federal Subsidies in Shaping America’s Energy Future .) So while I generally believe that most energy incentives should be phased out over time, I feel most strongly that we should start first by eliminating all incentives and industry specific tax benefits for those energy sources that have been receiving them the longest (in some cases for 90+ years). Once these are ended, then we could consider a gradual phase out of incentives for the newer renewable energy sources. However, if we do identify societal reasons to continue to provide favorable tax incentives for energy sources, then we cannot in good conscience end incentives for new technologies, especially clean renewable technologies that generate electricity directly where it is consumed, while continuing to provide favorable incentives and tax treatment for incumbent energy sources.

As my elected representatives to our US legislature, I am asking you to take the necessary steps to review and extend this solar ITC, in a sensible way, for a sensible time, with an appropriate phase out period. This would be a sound tax policy that provides the certainty necessary for Texas and American companies to plan for the future and to innovate; and enable more homeowners to experience greater energy independence. While historically, Texas’ great energy resources have been oil and gas, new technology innovation is allowing us to add wind and solar energy (including local on-site solar) into the mix.

I appreciate your collective experience and leadership in service to the citizens of Texas, and I look forward to having your support on this important home ownership and energy independence issue. I would welcome the opportunity to speak more about this important topic with you.

Best Regards and Shine On!
Richard Howe
Plano, Texas

This letter is from one of our Plano Solar Advocate (PSA) volunteers and does not specifically represent the views of other or all PSA volunteers. Comments and feedback are encouraged in the comment section below.

As North Texas Grows, Let's Grow it "Solar Ready"

Building a new home, or know someone who is?  Then make sure the builder designs and builds it "Solar Ready"!

North Texas continues to grow.  According to various estimates, the population could double over the next decades and along with that a million new homes could be constructed.  Providing clean energy will be one the key challenges for the region. However, with this new home construction, comes the great opportunity to leverage our local clean energy resource from the sun!

Studies have determined that not all existing homes are good candidates for rooftop solar installations, maybe only 20-33%. Home orientation, roof layout, and roof obstructions can be reasons for some homes not being a good candidate. However, new homes don't have to have these potential blocking issues. New solar ready building codes have been defined and included in the 2015 International Energy Conservation Code (IECC) for residential dwellings. 

Consider the parallel of rooftop solar with residential home air conditioning. Some 50-60 years ago, new homes being built began to widely adopt the new technology of residential central air conditioning.  The designs and building codes were adapted to accommodate the changes necessary to add this new major home appliance technology. It was a wonderful technology greatly increasing the comfort and livability for Texas citizens. So much so, the population of Texas began to grow dramatically.  Also at the same time, undoubtedly the electricity demand began to grow across the state, and in particular the peak demand began to grow with heavy air conditioning use during our long sunny summer afternoons.

Fast forward to today. Peak demand electricity usage has become a challenge for the Texas electricity grid.  And more people are continuing to move to Texas.  And more new homes are being built. Today, 50+ years after the wide spread adoption of residential central air conditioning, there is a new technology beginning to be widely deployed called rooftop solar photovoltaics (PV). Finally, each new home can be built solar ready or include solar panels that generate local electricity to help power central air conditioning and other home comforts. Electricity that is generated where it is consumed, reducing the strain on the statewide electric grid. 

In March of this year, the Dallas Morning News had an article titled "New North Texas communities woo residents with neighborhood farms, open space”.  In the article were statements like - Trails, open space, community gardens are “IN”, golf courses are “OUT”. I took the opportunity to visit a few of the developments mentioned in the article - Light Farms (developer Republic Property Group) and Windsong Ranch (developer Terra Verde Group).  While many of the new homes on display included great energy efficiency features, there was what I considered a glaring problem. There appeared to be no consideration in the design of the roofs of these homes for future solar installations. There were SO MANY roof surfaces, ridges, dormers, and strange roof angles. It would be very unfortunate if the next 50 years of housing stock being erected today was not taking into consideration the great new potential of rooftop solar to provide onsite local clean energy generation.

Solar-ready provisions include relatively simple items such as including a chase that goes to the roof for solar service lines, and a roof design that provides an area of unobstructed south facing roof surface where solar panels could be installed. When included in the original design requirements and done when the home is constructed, these solar-ready provisions should add little or no cost to the overall price of new homes. See ICC Approves Changes to Energy Code for additional information.

Readers are encouraged to promote adoption of solar ready codes where they live as outlined in the Best Management Practices from the North Central Texas Council of Governments Solar Power Initiatives project. See Adopt a Solar Ready Ordinance for additional details.

And MOST importantly, as consumers and customers for new home builders, let's make sure that we are requiring that our next new home purchase be one that is designed and built "solar ready" - or maybe even include a solar PV installation with the new home!

For additional information, go to our Useful Links page and scroll down to the section labeled "Solar-Ready Homes - Net Zero Energy Homes"

Shine On!
Plano Solar Advocates (LH)