Why solar is likely to power the Home of the Future

"Very few places had air conditioners when the technology first became available, and now it’s rare to find a builder who would create a new home without it." Solar is growing cheaper and more popular each year! Check out this recent article!

Why solar is likely to power the Home of the Future

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)

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)

Solar Ready Homes in Texas - Getting on the Radar!

Small steps can begin to make a BIG difference!

Back in July of this year, we had a blog posting titled, "Build Solar Ready Homes in Solar Rich Texas".  The objective was to recommend that local jurisdictions (and Texas at the state level) consider adopting residential building codes that require new homes to be designed and built "solar ready". 

Recently, the Texas A&M Energy Systems Lab (ESL) completed their mandated technical review and recommendations of the 2015 IECC and IRC energy codes for the State Energy Conservation Office (SECO).   Their letter of recommendation included a review and summary of the comments that SECO received regarding the 2015 codes.  (See section labeled "Comments in Favor of the Adoption of the 2015 IRC Appendix U: Solar-Ready Residences".) While "solar ready" provisions were not specifically recommended by ESL, it was great to see in this summary report that "solar ready" provisions are finally getting some visibility.  

Small steps can lead to BIGGER steps!  Let's keep promoting residential rooftop solar PV in Plano and all across Solar Rich Texas!

Shine On!
Plano Solar Advocates (LH)

Build Solar Ready Homes in Solar Rich Texas

Pursuant to 34 TAC §19.52, the Texas State Energy Conservation Office (SECO) is accepting written comments through August 4, 2014 on the energy efficiency provisions of the 2015 International Residential Code (IRC) for single-family residential construction and the 2015 International Energy Conservation Code (IECC) for all commercial and residential construction. These written comments can be provided by email.

(See - http://content.govdelivery.com/accounts/TXCOMPT/bulletins/c29371?reqfrom=share)

Included in the 2015 IRC is "Appendix U-Solar-Ready Provisions", an appendix describing provisions for building new homes solar ready.

Readers are requested to email SECO (at 2015CodeComments@cpa.texas.gov) no later than August 4, 2014 to encourage the state and local jurisdictions to adopt Appendix U as a requirement for new homes built across Texas.

Some background: 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 for homes 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. Not only because more people came to live in Texas, but because each home was using more electricity to power the air conditioning systems that were keeping us cool.

Fast forward to today. Peak demand electricity usage is becoming more and more of a challenge for the Texas electricity grid.  More people are continuing to move to Texas.  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 home can include technology that can 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. Electricity that is generated from local clean sunshine, not requiring our precious water resources like traditional centrally generated power plants. Electricity that is produced without air, water, or noise pollution.

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.

So please take the time to generate a brief email to SECO at 2015CodeComments@cpa.texas.gov and ask them to adopt "Appendix U - Solar-Ready Provisions" of the 2015 IRC as a requirement for new homes built in Texas. And ask others you know to do the same!

Shine On!
Plano Solar Energy Advocates (LH)

Additional thought - If you hear from a homebuilder that building a home solar-ready costs too much, ask them how much cost is added to homes to include fireplaces? How much time per year do you spend in front of the fireplace vs hours of sunshine?