This news flash about a seemingly obscure topic is of immediate importance to all our architect Title 24 clients -and it’s good news for a change. The Quality of Insulation Installation credit is a HERS test that can help design projects to achieve Title 24 energy compliance, and we’ve had a couple of nasty surprises with it in the past.

Apparently, up until around yesterday, the California Energy Commission did not officially recognize the QII test as valid for open-cell spray foam. Our insulation expert James Morshead of SDI Insulation actually sent me an urgent email yesterday with the news, saying:

Today the California Energy Commission stepped out of the 1980′s and into the 1990′s! The 1/2 pound density spray foam QII check list has finally been approved after long delays.

There will be further revisions and refinements but our State has finally caught up in its own way. They have finally acknowledged what the rest of the country has known and what we have known in our area for years; spray foam works whether its closed cell 2 pound density or open cell 1/2 pound density.

Now on to fixing the U-Value tables!

Active lobbying at the CEC is necessary

As usual, James was an endless trove of insider information. Apart from the news itself, the way that this came about was very revealing of the CEC’s  inner working processes. Most of us don’t understand how or why regulations are the way they are, or how agencies like the CEC solicit input from the public. Apparently one must be prepared to show up in Sacramento at multiple hearings, cultivate deep relationships with CEC staff, sift through the raft of proposed changes for the few items that might be relevant to your industry or situation, and be prepared to pounce on proposed changes with a formally structured submittal process. In other words, hire a full-time lobbyist.

A QII teaching case with the New Solar Homes rebate

We’ve run into some issues on the QII test before, where we’d called it out for extra credit on a Title 24 report on a project that was going for the New Solar Homes rebate. The house had to beat Title 24 by 15% to qualify. James Morshead was actually the insulation installer on that job, and clearly remembered how the HERS rater – NOT one of our Green Compliance Plus Affiliates – flatly refused to accept the low-density spray foam. Closed-cell was fine, but open-cell? No way. This was maybe the first time we’d ever used the QII credit, and nobody, including our other HERS raters, could tell us much about this obscure little omission that suddenly threatened the validity of the project’s energy compliance documentation – and the NSHP rebate. There was much tearing of hair and gnashing of teeth all around.

This close-up shows examples of open cell and closed cell spray foam, also known as low-density and high-density foam. Each cell in the high-density foam is closed, making it a better air barrier - which increases its insulating value.

Whys’ this QII change so darned important?

What are the ramifications of this change and how did it come about? “The recognition of open-cell spray foam has been in process for six and a half years,” said James. “We at SDI didn’t know how the CEC process worked. We thought the CEC would be actively looking at the market to incorporate new developments in a proactive way. But they’re not set up to do that. They’re set up to be reactive, influenced by lobbying input from stakeholders in the marketplace.”

He mentioned a long-ago fight between manufacturers of cellulose and fiberglass insulation, each of whom pushed to have their own products recognized as higher efficiency (higher R value) than the other. “That’s normal business. The CEC is a government agency, and that means that they’re encumbered themselves by a lot of regulatory process. They’re restricted by the system themselves. They rely on input from competing parties, and they solicit information by saying, ‘We want your input.’ They rely on the stakeholders to approach them and provide the necessary technical information.”

But presenting this input to the CEC can be an uphill battle. James mentioned meetings that would be cancelled without notice, web site meeting schedules that were not updated to reflect changes or cancellations, and a very skeptical audience. “They’re coming from an analytical and academic standpoint, but they’re NOT in the field.” And that’s the main point of this discussion, is that until the CEC actually went out to see a low-density spray foam installation, they didn’t believe it worked AT ALL. “They were writing regulations without ever having seen it in action.”

James went on to emphasize that he didn’t fault anyone at the CEC, in fact he admired their work and didn’t envy their task. They’re overworked, underfunded, well-intended, and very committed to the overall goals of helping California to achieve greater energy efficiency. They are doing their absolute best within cumbersome bureaucratic processes that they can’t change, either. To get an an idea of how slow the cycles are for code revisions, consider that the current version of the California energy code, the 2008 code, actually didn’t go into effect until 2010. And, some of its provisions weren’t enforced across the board until October of 2011.

Meritage Homes – a study in foam

Then we got on the topic of Meritage Homes, a high-end home developer who was apparently instrumental in adopting and demonstrating the real value of spray foam. Meritage’s Green FAQ page actually talks about the building envelope as separate from the appliances. James told me that Meritage had decided to use 100% spray foam in all its new developments. Their homes weren’t selling, because of the economy of course – not because the homes were bad. Nobody was buying anything, no one could get financing.

“But then, someone convinced them to foam their homes. The first batch was in Houston, TX. And the spray foam was so effective as an insulator that it ended up causing them some problems early on. Suddenly, all the A/C units in the foam-insulated homes were grossly oversized! Short cycling and such. And they had mold problems as well. But they also realized: OMG! this foam works way beyond the calcs!”

Meritage Homes is a high-end home development company that has implemented energy efficient building envelopes as part of the core design.

And that’s where we get back to the CEC, and the California energy code, which has all sorts of tables and appendices with the allowable thermal values that you can use for various types of wall assemblies and insulations: wood frame, metal frame, etc. (They even have an appendix table for straw bales now.) So, even if your insulation is NASA-quality, the CEC’s Joint Appendices might disallow the use of its true performance capabilities when doing home energy calculations. Which isn’t really fair, considering how difficult it’s been to get even ordinary home designs to meet current California energy standards.

The deconstructed home as sales tool

Most of the time, developers will have a few finished-off model homes that prospective buyers can walk through to see what their home will eventually look like once it’s built. But Meritage did something different. They had a model home with cutout walls to show the interior building assemblies, including studs, wiring – and spray foam insulation. “I call it the deconstructed home,” said James.  “People now are smarter, more educated about building and energy efficiency. They want to see what’s inside. And sales took off! It was a totally new way to sell houses. Local building inspectors liked it, too.”

The homes weren’t selling for more money, but they were selling a lot faster – and, to investors, time is money. The quicker you can recover an investment, the less financing costs you have.

By showing a "deconstructed home" rather than the usual finished showcase model, Meritage Homes has educated homebuyers on construction techniques and efficient building envelopes. This image shows a deconstructed Meritage home from one of its San Antonio developments, as shown on housingzone.com.

CEC’s focus on new construction ignores issues for remodels

Then our conversation touched on another issue with the current California energy code, and that is its almost obsessive focus on NEW construction. One goal at the CEC is for all new homes built after 2030 should be Net Zero. But remodels to existing homes also impact the energy grid, and at least in California, remodels right now represent a significant portion of current construction activity. (This is according to James – I haven’t yet found any data specifically comparing either dollars spent or number of projects of each type, in CA).

Sometimes this results in a very artificial situation when we try to show compliance for a remodeling project. It becomes an exercise in hoping that the project qualifies for prescriptive and we don’t have to run an energy model. For example, if a remodel is not adding any square footage, but the total glazing area is over 20% of the floor area, there are situations where the project just doesn’t qualify for prescriptive compliance. And let’s say that this is a low-budget project; they’re changing out the heating system and enlarging a couple of windows and leaving the rest alone, maybe it’s mainly an interior remodel which doesn’t affect the building envelope.

Well, there are times we’ve had to run a whole-building model that included all portions of the existing home that aren’t being upgraded, but which aren’t built to current energy standards. It’s easy to go down a path of adding new energy measures that not only add to the cost of the project, but which can just get ridiculous. Open more existing walls to re-insulate? You could trigger a seismic upgrade. Replace all the windows? Well, maybe the old windows were still perfectly good, why throw them away? Is that “sustainable building”? I’ve spent hours reading the Residential Compliance Manual’s sections on alterations and remodels, and sometimes writing to the CEC, to find out what’s really allowable.

Trying to get a small remodel to pass California Title 24 compliance can be more agonizing than modeling new construction. This vintage contortionist image is from "The Circus, 1870-1950" published by TASCHEN.

QII checklists for each type of insulation didn’t include one for open-cell spray foam

James reminded me that the HERS rater has to follow different QII checklists based on which type of insulation is used in the project. So there’s one QII checklist for fiberglass batt insulation, and a different checklist to use for blown-in, etc. Here’s a nice checklist writeup from ConSol, an energy group based in Stockton.

This checklist does not affect allowable R-values used in the Title 24 performance calculations. All it does is say that insulation should be installed evenly with no air gaps, empty spots, or compression, and that wall cavities should be sealed to limit air flow through permeable insulation types. The extra credit is really a make-up because the assumption is that typical insulation installation procedures are so shoddy that substandard installations are the norm rather than the exception. So, what’s not to like about open-cell spray foam exactly? And yet, because the CEC had no official checklist that was specific to open-cell, and they didn’t want to lump open-cell and closed-cell together, the omission has led many HERS raters to conclude that low-density spray foam was simply not allowed for the QII credit. That may in fact have been the official CEC policy, too.

Some HERS raters have very extensive backgrounds in building efficiency, construction, and green building; others just don’t have the same depth of knowledge. That’s one reason we chose to list some HERS raters on Green Compliance Plus who we felt had a better grasp of the underlying principles behind Title 24 energy compliance. Our HERS rater affiliates are people with multiple credentials: some are HERS and GreenPoint Raters, some also have CEPE certification, and most have other creds ranging from Energy Star to BPI to LEED for Homes. They already have experience working with integrated project teams on custom home projects, and are more proactive about anticipating potential situations ahead of time or recommending solutions instead of just showing up for the inspection and saying, “Well, you fail, and there’s nothing I can do to help. You won’t get your rebate after all. ‘Bye, now.”

The CEC doesn’t always realize these ramifications until they’re pointed out

On the above mentioned NSHP case study, when James brought this up to the CEC staff and engineers, they were appalled. They had never dreamed that their policies would ever lead to a situation like this. The HERS rater had said, rather erroneously, “This product doesn’t work. Therefore, it’s not allowed.” What he really should have said was, “This product doesn’t have an authorized CEC checklist. And it’s still not allowed.”

Checks and balances to prevent cheating are well intentioned, but they can really gum up the works

“The CEC really wants to discourage cheating,” said James. There are certainly more steps to verification now than in the 2005 code. The whole CalCERTS registry process, with online filing of  the tandem forms for the Title 24 energy compliance report, the installation certificates, and then the HERS certificates, is a great idea but a royal pain in the bum. The online workflow is especially agonizing for custom remodel projects. The CalCERTS support folks are very nice and they also have to follow a ton of regulations that attempt to cover every possible home construction scenario; they’ve never had to consider a different workflow for custom homes where an architect is directly involved.

The code update process is complex and unforgiving, not unlike San Francisco’s planning and approvals process.

So – what if someone wants to advocate for, say, a better attention to remodels, or to custom architect-designed homes? You’d better have a full-time staff person on the job. “The process is so cumbersome, with hearings, submittals, and a lot of 45-day language,” said James. (Really it’s just like the SF planning process) “It’s really arcane – miss something and you’re dead.”

Other industries have their own issues to push for in the energy code. “HVAC, energy consultants, builders… there are a few people who practically sleep in their cars down at the SMUD building in Sacramento.”

It helps to establish a good rapport with the CEC staff, who got high marks from James for dedication and responsiveness. “If you know the system really well, you can know which events are important, but you can’t tell just by looking at the CEC site. It’s a labyrinth, and you need a guide. Try to have a relationship with the CEC staff. They can help you get your voice heard.”

Is the Net Zero goal realistic and achievable by 2030?

James thinks that the goal of having all new homes built in California after 2030 be Net Zero Energy is unrealistic, and not the best way to reduce overall building energy use statewide. “NZE should be affordable to more people than it is right now. We should be making it easier for people to comply even as we tighten the standards. It would be better to reduce energy consumption by 40-50% rather than try for some exotic concept like Net Zero. Go for more basic stuff – air sealing, HVAC sizing, more credit for unventilated roof assemblies.”

“Net Zero Energy is a great idea,” he continued. “But in the construction industry, there are so many different kinds of people involved. There are builders large and small, plan checkers, building inspectors, HERS raters, architects, energy consultants… no one knows how to do it right yet when it comes to energy compliance. Right now, this education is being force-fed into the system when people aren’t ready. NZE is such a complex concept, it requires a very integrated approach. If you push it on people too fast, it’ll be a disaster in the implementation.”

I can’t argue with him there.

Of all the green building guides for homeowners out there, here is one that should be on everyone’s shelf – owners, architects, builders alike. It’s called “Energy Free: Homes for a Small Planet” by Ann V. Edminster, a Bay Area local. Everything I’ve been struggling so hard to explain to our Title 24 clients, even in a limited way, is presented in this book with clarity and accuracy, in a very readable and lively prose style. It’s backed by both the latest research and by personal experience and observation.

The Problem with Mantras

“They want it to be ‘green’…” Neither the client nor the architect had any comprehension or appreciation of “green” other than as a gimmick. The client was an Al Gore fan who had read “An Inconvenient Truth” and suddenly decided mid-design that the new house being designed for him and his girlfriend needed a “zero carbon footprint”. There had previously been vague feel-good conversations about “eco” and “green” but nothing tangible, no specific goals, performance measures, or standards to follow. Unfortunately, neither the client nor the architect understood how much work “zero carbon” actually entailed, and the client hadn’t selected this particular architect for his expertise in green building. He had originally envisioned a luxury home by a “design-oriented” (i.e. Modernist) architect.

"Green zombies" chant the green mantra endlessly, but never stop to think about how to get there.

I can’t tell the whole story here, but it seems that the client was shocked to hear that there might be re-design fees involved, plus a fair amount of additional research. (He and his girlfriend split up in the middle of the project, too – the project was subsequently abandoned.) Perhaps he felt that anyone calling himself an architect should already have the answers. That’s a bit like saying the architect should already have the house designed the moment you set foot in their office.

First, Take A Good Look in the Mirror

But choosing green can be daunting – as if shelling out several hundred thousand dollars or a few million for a custom-built home isn’t daunting enough. If you’re seriously trying to be green, there are so many competing standards and methodologies out there, it can seem overwhelming. And to be honest, there is no shortcut to thinking hard and seriously about it as an owner. You’re not just learning about technology, you’re taking an inventory of yourself, your habits, the real implications of those habits, and what you could do without. It’s also being very honest about what you can’t live without and sticking to your guns about it – even if that need might seem “selfish” rather than “green”. You can’t just engage with an architect, wave your hand like Captain Piccard on Star Trek: The Next Generation, and say “Make it so.”

The hardest work of green design is asking yourself what's really important, and then following through

What we need is a simple guide on HOW to think about building green, meaning how do you go about deciding what your priorities are and then executing them to completion? How do you even define what’s green, or green enough? What kind of science is behind each of the green definitions, anyway? It’s an exercise in complex problem solving – and self-analysis.

Start With Home Energy Consumption

Measuring greenness according to energy consumption is fairly straightforward, and while that can’t capture everything related to embedded energy, building life cycle, etc., it is the sort of bottom line that anyone who can balance a checkbook can understand. And finally, we have a book that talks turkey about how do we get from being energy-dependent to a point where we’re more in control.

“Energy Free” manages to provide clear guidelines without being too dogmatic about any one thing. Edminster’s focus is on energy efficiency as a means to reducing our dependence on oil and other fossil fuels. Along the way, she exposes a lot of myths and misconceptions about what it really means to produce your own energy instead of relying on “the grid”. Although this approach is sometimes called Net Zero, she prefers to call it energy-free, because you’re freer, more liberated (to a point which YOU determine).  It’s both a manifesto and a guidebook for creating and enjoying a net-zero-energy home.

Determining That Net Zero Point

The first debunking is to explore what NZE means. For example, producing as much electricity as you consume onsite doesn’t take into account transmission losses from the power plant to your house. Also, you have to use different conversion ratios depending on the type of fuel you use (electric, gas, propane). In the case of electric power, the type of fuel used at the power generation plant can affect how “green” or “wasteful” that electricity really is. This forces the owner to confront his or her own principles at the get-go. How far are YOU willing to go and what will you get out of it?

Then there are practical questions about Net Zero. Will it actually save me money? Can I use the same builder? What are the real-world pitfalls and how do I avoid them? How do I manage the project? Who needs to be on the team, and when? Edminster does a superlative job of capturing the key drivers and human factors that can make your NZE project a success.

No One-Size-Fits-All Solution

Our culture of instant gratification and ever-shrinking attention spans does not lend itself to complex, thoughtful, tailored solutions. But, after clearly defining your principles, goals, and budget, the next thing you need to do is realize that every solution is local and is dependent on context. What works in San Diego may not make sense in San Francisco. And, concerns that are important for surviving a Massachusetts winter might not matter in San Jose.

A radiant barrier won't help as much in Tahoe as it will in Death Valley. Different climates call for different measures.

Edminster’s approach is to treat it like a team science project, and to keep everyone focused on the performance goals. It’s one thing to say that passive solar designs are nifty, but it’s better to start with some specific goal (and location), and then identify all the different ways one could achieve that goal. KNOW what your goals are, and be prepared to read the fine print – like which measures actually make sense for your climate zone. But don’t forget your personal goals, or you won’t be happy with the end result. A happy home takes more than just low-flow showerheads, and everyone on the team should appreciate this fundamental notion.

Your Team

This is something that other Green Builders have said, but it’s worth repeating, since we say it to our Title 24 clients as well. If you want a high-performing home, think farther ahead to make the best design decisions possible, and get your experts all talking to one another during the early design stages. And don’t use a compartmentalized series of handoffs, which unfortunately is the standard way of doing business in the homebuilding and home remodeling industry. Make sure your team members can work well together (that includes you) and that everyone starts on the same page. This is referred to as “integrated design”.

Green building requires a long-range planning approach, rather than a moment-to-moment response.

The skill sets are also different. A typical, non-integrated team might have an owner, a builder, and an architect. Other consultants might be brought in as needed but they have limited influence over design elements not in their immediate purview. They probably don’t have any visibility, either.

A compartmentalized, "handoff" approach might look like this Gantt chart.

In addition to the owner and builder, an integrated team might have a mechanical engineer, an energy modeler, possibly a structural engineer, and a renewable-energy vendor. All of these individuals need to be part of the initial design process, so that they can understand the wholistic impact of each proposed design element – and the reasons behind that impact.The team must have a clear common understanding of the goals of the project, in order to determine whether a particular impact is acceptable or not.

Start by Scoping Down Energy Needs

It makes sense once you hear it. Minimize the home’s energy budget before sizing any renewable energy systems. You do this by a multi-pronged approach that includes building, appliances, and occupants. The building should be efficient and not oversized; appliances should be not just Energy Star rated, but top of the chart; and occupants should be educated on things like how much energy a plasma TV REALLY uses.

Downsizing on floor space might be a hard pill for some people to swallow, but it’s really only going back to what homes were like in the 1950s, when the average was 292 SF per person. Now, it’s more like 961 SF – a threefold increase. Do we really need that floorspace? Or could some of it be outdoor space, or transitional space that doesn’t need conditioning?

This rather cramped attic is actually from Lawrence Welk's childhood home. A far cry from McMansions!

This Time, You Should Sweat the Little Stuff

Next come the appliances, lights, and electronics. What can you scope down or trade for a more efficient model? What can you eliminate? What energy management systems are there to monitor usage and to shut off appliances when not in use? What about water heating? Do you need that spa, or would a compact steam shower do almost as well?

Almost every item in the house offers opportunities for reduction, from faucets to lighting fixtures. For energy nerds, the lengthy discussions of just how much extra energy is used by the heating element inside your dishwasher will be glorious. But actually, everything discussed is in response to frequently raised questions about things like whether a measure really saves resources or not.

The section on building efficiency goes on for pages about different types of insulation, but even better were the detail sections showing sheathing, insulation, and airtightness. Everything from mold prevention to stack ventilation to solar heat gain. Without playing favorites, there’s a huge section on heating and cooling systems and how to get the most out of each type. There are even piping diagrams for hot water delivery.

But the best thing? An energy-modeling chart showing how the influence of different building parameters changes by building type and climate zone. For example, window area and solar heat gain was more important on the “urban” single family home in Palm Desert, but of lesser importance on a low-rise detached home in San Francisco. Surprisingly, building orientation did not have as much of an effect as one might think, except for the urban home in Palm Springs.

Living Patterns and Appliance Use

One thing I liked about the chapter on integrated design was the emphasis on behavioral factors and living patterns. For example, an owner who is away from the house much of the time might have different preferences than someone who is there all the time. Some owners may be willing to change their behavior or their tolerances as well. For example, foregoing heavy air conditioning in favor of the old Mediterranean tradition of afternoon siestas, or wearing a sweater on chilly mornings.

Putting on one sweater on a cool day might be better than immediately turning up the heat. But, if you have to wear a parka and frosbite protection indoors, the house is probably too cold.

As with HVAC systems, the discussion on appliances and their use is exhaustive. Everything from induction cooktops to dishwashers (including when to hand wash and when not to), gardens, gadgets, and monitoring systems. The only thing missing was the obligatory rant on the mercury toxicity of CFLs. (I personally feel OK about them – I can see better and they cost so much less to operate than my favorites, the halogens.)

Quality Construction

Even the fanciest windows won’t save as much energy if the builder does a poor job of installing them. The same applies to everything else: walls, systems, plumbing, ductwork. Each part of the whole should be optimized and well-crafted. Unfortunately craftsmanship is not a given for all builders, although they’d like you to think so.

Post Construction Verification

Much of the information presented in this book came from the author’s direct experiences. Just because an energy model predicted a home that uses 25% less energy, does that mean that the actual owners will use less energy once they’re living there? What if it’s too hot, or too cold, because of some factor or complex interrelation of factors unique to the site? What do you do then? Usually, with good planning, remedial measures will be minor, and can be anticipated, to be used only if needed.

Please note that we have no commercial interest in promoting Ann Edminster's book "Energy Free" - we truly think it's a great guide to planning your home energy strategy.

While researching solar technologies, we at Green Compliance Plus heard from solar installers  who all seem to think that architects are hard to work with. So, we spoke with Fernando Valenzuela of Alter Systems in Berkeley about how to design a solar-ready home. Note that only about 5-10% of Alter Systems’ customers are owner/architect teams. Usually it’s the homeowners approaching them directly because they want to “go solar”.

So… why are architects hard to work with? “They have a groupthink… they like design, the look, but they don’t understand systems. They ask questions like ‘why can’t we use this roof’ without realizing that you can’t split up an array. Their projects aren’t always quick, either, and rebates that were designed for may be gone by the time the project gets through approval.”

Valenzuela went on to provide various design tips, as well as insights into new technologies, best-of-breed products, the difference between grid-tied and off-grid systems, costs and returns compared with conventional power, financing options, and the importance of grid parity.

Solar Design Tips for Architects

Consider building shape, roof planes, and orientation: With a remodel, people engage with an architect after the house is already built. It’s really best to take solar into account and design for it from the start. This may include choosing a lot or site that allows for a good solar orientation. Assuming that you do have some power to determine the shape of the building envelope, just make sure you include a nice un-shaded patch of south facing roof around 20 x 30 feet for your PV arrays. It goes without saying to consider proper solar orientation for the building, of course, if you have the option to do so.

Until recently, a single contiguous area was needed for solar arrays, and many products are still configured to work only if all the panels are installed together as a group. The panels should be tilted for maximum solar angle. Some panels lay flat and others can be tilted up; flat panels are aesthetically preferable and better for the neighbors’ attitudes.

Optimize roof tilt: The optimum tilt for the solar panels is your the latitude minus 15 degrees. In California, allow for a south or west facing planar area that is tilted around 20-22 degrees. Utility-scale projects and off-grid systems sometimes use solar tracking devices, but typically residential panels are mounted in a fixed position. The “solar window” is the maximum energy harvesting hours, between 9am and 3pm.

The sun's path across the sky changes according to season.

Assuming that you design includes panels that are built directly into the roof, your roof tilt will determine the panel tilt. “Not too steep, either, ” says Valenzuela. A 30 degree roof tilt is too steep – it’s much harder, and more dangerous, to install the panels. “It works your abs and butt!” laughed Valenzuela. And it’s not exactly “green design” when crews get injured, is it?

The roof tilt also depends on whether you have a grid-tied or an off-grid system, according to Valenzuela.

• Grid tied should be your latitude minus 15 degrees. Grid-tied systems are optimized for summer, because that’s when you’ll get the most energy out of the system, and thus you’ll get more money back at the end of each year.
• Off grid, on the other hand, should ideally be your latitude plus 15 degrees. For off-grid you maximize for winter, because you need the system working even in the worst-case scenarios so that you’re not left in the dark. Basically you want to make sure the system will produce in the winter months.

Allow space for conduits: If solar power is an afterthought, then you may have a visible exterior conduit, which can be less aesthetic than building it into the wall. If you put the conduit under the sheetrock it won’t even show on the outside. But even if you’re not installing solar today, you can accommodate future solar in the design.

Left, a typical retrofit requires routing the conduits wherever you can. Right, allowing a place for solar conduits that's built into the house allows flexibility for future solar.

Be careful with vent placement. “Don’t put vent pipes in the middle of a rooftop solar array. If the pipes stick up too far, they’ll get in the way of the PV panels.”

Make the roofing strong. Roofing should be 2 x 6 or 2 x 10 at 16″ on center for strength. Modern codes want 2 x 4 at 24″ across to conserve materials. If the span is too long, however, this doesn’t account for the weight of the people walking on it to do things like install solar panels. For this purpose, spans over 8 feet need thicker rafters. “We do a lot of retrofits,” says Valenzuela. “Old buildings in Berkeley for example are often 2 x 4 at 24 off center. For these, we may have to put in a brace.”

Keep basic sizing guidelines in mind. The amount of surface area you need for your PV panels depends on how effective the panels themselves are, and how much power the house requires. A rule of thumb might be 500-600 SF of roof (or other area) for the solar array to generate 5 – 7 kW. This covers a lot of places, even desert climates. “Even in the hotter parts of California, with heavy air-conditioning loads, it’s not too far off base,” according to Valenzuela.

Understand the racking systems. It’s good to understand how racking systems operate. “No roof penetrations” are needed. In the future, each panel may come with an independent energy panels with built-in inverters. Innovations include reduced installation time and cost.

Process

Choosing Your Solar Companies: A solar systems company is essentially a contractor/consultant who supplies, specifies, and installs systems. “If your client wants solar power for heating, cooling, electricity, or water heating, then you as the architect will need to establish a good relationship with a company that you can rely on to supply a well-designed system that is appropriate for the programmatic requirements of the home.”

“Try to work with a few solar systems companies that you know well, to get standard products and sizes for components. But don’t rely on just one company, because some companies are over-scheduled right now and orders are going unfulfilled.”

How Long Does It Take? Allow a month turnaround including all permits and paperwork such as rebates.

Customer Experience: So what happens when someone comes to you and says they’re ready to go solar? Here’s what your clients can expect.

1. Site evaluation. The solar consultant will most likely want to visit the house to inspect the roof area, shading, and electrical box. Some houses just aren’t suitable for solar. “Usually it’s a mounting problem,” says Valenzuela. A general rule of thumb for say a 1,200 – 2,000 SF house is to have flat or south facing roof around 20 x 30. Using micro-inverters helps reduce the amount of roof area that you need (read on for more information).
2. Proposal. Assuming the house will support a solar system, the owner gets a price proposal. “I have to ask why they’re doing it to figure out if it’s off-grid, grid-tied, or hybrid system. If they sign off, the paperwork starts.”
3. Permits and Rebates. Local permits for installing a solar system can take as little as a day or up to around 2 weeks depending on locale. The paperwork for tax rebate programs takes 2-3 weeks.
4. Installation. Alter Systems takes 2 days to install, but schedules for 4 days to allow for contingencies such as rain. The owners or occupants can continue to use the home and live in the home while the installation is ongoing.

Grid-Tied and Off-Grid Systems

One basic decision the owners must make is whether to tie their new solar arrays int the power grid. Grid-tied and off-grid systems are totally different animals in some important ways, but as solar power gains mainstream acceptance, it must also be able to integrate smoothly into mainstream infrastructures as well.

• Off-Grid systems are the classic “1.0″ of solar renewable energy. Although they tend to be associated in the U.S. with environmental activism, survivalist movements, and early-adopting technology buffs, they’re also essential in parts of the world where a centralized power infrastructure either doesn’t exist or isn’t reliable.
• Grid-Tied systems are mainly intended to reduce or eliminate energy bills, as in Net Zero homes. It’s a more mainstream market than either the early adopters or the green contingent. A main motivation is likely to be cost savings.

Although grid-tied systems are a newer concept, they are likely to be the wave of the future in industrialized countries. The components of a grid-tied solar system are the panel arrays, a power inverter to convert the direct current generated by the panels into the alternating current used by household appliances, a manual power disconnect, and of course the utility company’s usual infrastructure: the meter and switch box.

A grid-tied system is simple and straightforward. There is no need to store power onsite. Power generated is fed directly back into the grid, and home power needs are drawn also directly from the grid.

An off-grid system has more components, because of the onsite power storage requirement. In an off-grid system, the solar arrays feed into a combiner box which balances the inputs from each array. The combiner box combines or branches together the PV arrays/modules and then takes all the power through one set of leads to the charge controller. The controller makes sure your battery is charged correctly, and prevent over-charging.

The advantage to this type of off-grid configuration is the ease with which you can add supplemental power-generation systems such as microhydro or wind turbines. The goal of an off-grid system is to keep the batteries fully charged at all times. If there’s a grid tie-in, the battery won’t “sell” back to the grid unless it is already fully charged.

Which configuration you choose for your solar system depends on the reason why you’re going solar in the first place. Homeowners typically adopt a grid-tied system to save on energy bills, reduce their carbon footprint, and perhaps to show off to their neighbors. Valenzuela cites an estimate from the Journal of Assessors and Appraisers that for each dollar you can shave off your annual home operating costs, you add $20 to the property value.

According to Valenzuela, based on his experiences with his own customers, homeowners might choose off-grid because they’re in a remote area, and either it’s too expensive to bring the grid out there, or it exists but is not completely unreliable. “Some people do it because they hate public utility companies just on principle,” notes Valenzuela. “They’re also more likely to be DIY types who are comfortable assembling their own systems,” he adds.

An off-grid system includes an onsite storage battery. It's designed to be self-reliant. The homeowner can add a grid-tie option as shown above.

So what are the pros and cons of each type of solar configuration? Grid-tied systems require less equipment and employ simpler configurations; on the downside, they’re limited based on inverter sizes.

With off-grid systems, it’s easier to add supplemental renewable-energy systems on the side for things like wind or microhydro.

It's easier to add supplemental power generation systems to an off-grid system with its own battery storage.

Off-Grid for Villages: A typical residential home might need a 6kW system. For sites such as an army base, a remote ranger station, or a farm with multiple buildings, a system called AC coupling can deliver 20 kW or more. Basically it’s a way to create your own micro-utility company, and collect power from solar arrays on several buildings, using one central inverter (such as the Sunny Island off-grid inverter from SMA Solar Technology) and a central storage area. “This type of installation is very useful in places like the Caribbean, island countries or places without any infrastructure,” says Valenzuela.

Could you implement something like that in a city neighborhood, I wondered? A residential collective of some sort, for people who live in urban areas but still want to have totally independent self-generated power, and who want to pool their money to invest in economies of scale? “You’d have to do all your own wiring,” Valenzuela responded. “They’d have to be fairly close together.”

Well… with the geek factor in this area of the country, I wouldn’t be surprised if it’s already happening. After all, if a few homes drop off the grid on a single city block, how would we ever know?

Solar Grid Parity

I didn’t even know what this was, but with all the talk about the ROI of solar systems vs. fuel cells vs. high-efficiency but conventional systems, it’s a very important concept. Solar grid parity is a tipping point in the energy marketplace when the cost of energy production for solar power will be equal to or less than the cost of generating conventional, fossil fuel-based grid power.

A common comparison is dollars per watt or cost per kWh. U.S. average power prices for last year ranged from 5 – 15 cents per kWh, averaging roughly around 10-11% (businesses were 1 cent cheaper).

This number includes upfront investment in equipment although of course there’s debate over how to calculate it and when this momentous day will actually come. 2012 seems to be a common guess, although coincidentally that’s also the end of the world, according to the Mayan doomsday calendar).

Prediction: “a number of solar companies will hit a long-pursued industry target of $1 per watt by 2012.”  This “race towards $1 per watt” means that “within a few years solar panels will be able to generate electricity cheaper than the grid in many regions of the world.” (Sunnier regions have a bigger solar payoff, not surprisingly.)

Another claim is that we can reach 2012 grid parity in “almost half the US” and he also notes that there are several ways to calculate grid parity.

Even 4 years ago, solar was still pooh-poohed as a boutique technology for wealthy do-gooders or conspicuous consumers. But that was before tax rebates and stimulus dollars made it easier for new owners to “green” their homes. Other factors include improved component efficiency and a wider array of creative financing options such as these options from SunRun to purchase solar power as a service, to lease the equipment to the owner, or to help owners seek solar financing through local municipal programs.

So, is it a sure thing that in 2012 we’ll all be putting PG&E out of business? Doubtful, but there’s definitely a sense that price parity is coming, it’s just a matter of when. For example, higher interest rates could hurt financing, and if grid prices fall, parity won’t be reached nearly as soon. For those who prefer to focus on equipment efficiencies, there’s a rather geeky engineering article from BP Solar that discusses current and future efficiencies, including emerging new technologies such organic photovoltaics and nanocomposite solar cells.

The $1 per watt number is disputed as overly simplistic on one investor blog: “PV’s competiveness with the grid varies wildly based on the region… The idea that module prices need to come down to $1/W for solar to be competitive is misplaced at best” because “PV is already at or near parity with the grid in a number of markets”. This blog also includes a good discussion of calculating the cost of various types of conventional power, including nuclear.

Solar Financing Innovations

For homeowners who want to finance their solar installation, three good sources are:

• Tax rebates
• Municipal funding options through property taxes
• Bank loans

In the second case above, this is a plan being adopted in some localities such as Santa Rosa. Basically, the city obtains the funds for solar installations at a very low interest, say 3%. The city then loans it out to homeowners at a slightly higher but still reasonable rate, say 7%. The owner then pays back the loan in the form of an extra property tax surcharge every year. If the house is sold, the new owner is responsible for continuing those payments as part of the home’s property tax bill, and the new owner of course enjoys the reduced energy bills in the meantime.

“Some owners just pay for it with a credit card,” said Valenzuela. I can’t imagine plunking down $35-$60,000 on my card but then again, I can’t imagine watching the national average of television, either. “Every dollar decrease in operating cost adds an extra $20 in property value,” said Valenzuela, “but equity is fake money. So, we don’t include this increased equity on our cost/benefit analyses that we show customers in our proposals.”

New Solar Products

During the course of our conversation, Valenzuela mentioned some of his favorite new solar technologies. In no particular order, here they are.

Solar forced air heaters. These devices are installed on a south-facing wall or roof and are best used as a complement to other heating systems, a boost but not a replacement. They’re small and relatively efficient, at least compared to PVs. A single 8-foot panel is enough to heat a small room. They use no fuel and have no moving parts except a fan to draw cold air into the panel and push heated air out directly into the room. They don’t work as well on cloudy days, obviously. And you don’t even need fancy PVs or heat collectors: here are some ingenious DIY solar air heaters made from recycled aluminum cans.

This 8-foot solar wall air heater from ClearDome Solar in San Diego can heat up to 500 SF of residential space.

Micro-Inverters. Green Compliance Plus has mentioned the breakthrough of micro-inverters in a previous post – basically, by having separate inverters for every PV panel in a solar array, you can harvest more energy because shaded panels no longer bring down the performance of the entire array. One maker of micro-inverters is Enphase Energy. Valenzuela waxed almost poetic about Enphase products: “At the recent Green Building Expo, their booth was mobbed while the big players were empty!”

FLEXpower ONE Off-Grid Solution. Valenzuela made special mention of one particular product from OutBack Power called the FLEXpower ONE. He recommended this for total off-grid systems including smaller installations such as boats.

Xantrex XW Grid-Tied Solution. The Xantrex XW from Schneider Electric is recommended for homes that are grid-tied with a battery backup. “It’s not quite as flexible as the OutBack for very small installations, but it’s easier for designers, because it’s a high-quality product and you can scale it up,” says Valenzuela.

But what should architects really know? “Use Enphase!” says Valenzuela.

Nearly every week, we are asked why Title 24 does not give credits for electric water heating if that electricity comes from solar or other self-generated power. In fact, it seems that many of the renewable energy developments occurring now are not fully recognized in Title 24, not even in the 2008 code. We’re in the position of telling people that their homes, which are designed to consume very little conventional power, may have trouble passing the Title 24 code if those homes rely solely on solar electric for all their home power, heating, cooling, and water heating needs.

So why does T24 continue to penalize electric resistance heat and water heating in solar homes? Why does T24 not give credits for self-generated power (geotherm, solar, wind, other)? And why can’t our utilities buy back excess power from customers who generate more than they use? Wouldn’t this help to reduce California’s grid load, save California homeowners money, provide entrepeneurial opportunities, and reduce American dependence on foreign oil?

Title 24 History

California’s energy standards were originally mandated in 1974 by the California legislature, through a piece of legislation commonly known as the Warren Alquist Act. This act created the California Energy Commission and authorized it to develop and maintain energy efficiency standards for new buildings, and it specifically requires that these standards be cost-effective “when taken in their entirety and amortized over the economic life of the structure.” (Title 24 2005 Residential Compliance Manual)

According to the Title 24 2005 Residential Compliance Manual, Title 24′s stated intentions are the following:

• Save homeowners money
• Keep homes affordable
• Reduce strain on the power grid during peak times by reducing demand
• Stabilize California’s economy by buffering against sudden price increases
• Comfort (poorly insulated and drafty homes with oversized systems that cycle on and off are less comfortable)
• Reduce environmental pollution
• Reduce carbon emissions

California Energy Commission’s Response

I started with the California Energy Commission, which is responsible for creating and updating the Title 24 energy code. Why would the code ignore the potential of self-generated power to reduce demand for conventional power when our grid is already fragile? I spoke with Mazi Shirakh, P.E., M.B.A., a Senior Mechanical Engineer who serves as the Project Manager for Building Energy Efficiency Standards at the CEC, and who is also the Program Lead for the 2008 Standards update. Mr. Shirakh outlined the reasoning behind Title 24′s approach to alternative energies. (It is normally the Commission’s policy that individual staff members should not be named in articles and blogs, but in this case they’ve agreed to allow us to attribute directly.)

“The reason is that up until now, alternative energy technologies were too expensive when compared with more traditional energy-efficiency measures such as high-performance windows or air conditioners. While their costs remain high, PVs cannot demonstrate cost effectiveness as required by the law. We recognize that this is changing,” explained Shirakh.  “PVs are still expensive, costing around $8/watt. To install a 2Kw solar system costs around $16-$20K, whereas you can get a high-efficiency furnace or air conditioner for a lot less than that. However, the price of PVs has been steadily decreasing since the beginning of 2009. Assuming that this trend continues, there will be more possibilities for PVs in the future rounds of Standards. At around $2 or $3 a watt (including incentives) PVs would be much more competitive with traditional efficiency measures.”

Shirakh mentioned incentives such as the New Solar Homes Partnership, and I pointed out that such programs have nothing to do with Title 24′s internal scoring. If the intent is to reduce the load on the grid through less use of conventional power, why should an electric water heater that runs from PVs be scored the same as an electric water heater that runs on conventional power?

“The building must meet a certain efficiency levels first before PV or other on-site systems are considered. If we didn’t do this, there would be nothing to stop someone from building an inefficient structure and just slapping an array of PVs on the roof instead of other efficiency measures such as building insulation. And there’d be nothing to stop the owner from ripping out those PVs later on and running the building solely off the grid.” he replied.

OK, I’ll buy that for a dollar.

Alternative energy contractors are less inclined to accept this argument without comment, however. “That’s a spurious argument, in my opinion. Who’s going to take a building with a functioning solar system and rip it out?” said Gary Gerber of Sun Light and Power, a solar systems designer and installer. Another alternative-energy contractor, Greg Kennedy of Occidental Power, speculated that it was about centralized versus decentralized power networks. “Utilities are building big centralized power plants, with solar installations far out in the desert and then transporting the power over long distances. If that power were generated more locally, less of it would be lost during transmission. It’s really about who’s controlling the cash register.”

In a subsequent exchange, Shirakh clarified CEC’s position regarding Title 24′s approach to self-generated power: “Allowing proper credit for solar assisted electric water heating is one of the goals of the next round of Standards (currently known as the 2011 Standards). However, we need to be careful about how much credit is given to onsite generation measures; we still want to encourage buildings with efficient envelopes, mechanical, water heating, and lighting systems, even in the presence of PVs and other onsite generation systems. In addition, an energy efficient building will require a smaller solar system (less costs) and provides more comfort to the occupants. It should be also be noted that the Standards do allow a substantial credit for solar thermal water heating which can be combined with either natural gas or electricity. This is a mature technology and is widely available within the State.”

Shirakh was not familiar with fuel-cell technologies such as ClearEdge Power’s product offerings. However, he assured me that if we did any Title 24 documentation for a project that used them, we could contact the CEC for assistance.

Does Renewable Energy Comply with Title 24?

So, how hard is it to get a net-zero home to comply with Title 24? “Most are quite easy, because they are relatively efficient buildings already,” responded Dave Knight of the Monterey Energy Group. “The coastal areas and the hills are OK, but it is significantly harder to get a net-zero home to pass in Central California. California’s central climate zones are very hot, and the A/C load kicks in.”

Knight added, “From the very beginning, Title 24 mandated that solutions be cost-effective. In the past, some systems such as solar thermal could supply 80-90% of a home’s space heating load, but were seldom cost-effective, and it was complicated to predict how they would work. But they’re not looking at the current prices or the latest incentives. In the last few years, the prices of solar PV have dropped by 20-25%. So there’s three things coming together now: more efficient buildings, lower PV prices, and new tax incentives.”

So What Can We Do About It?

“The Grid-Tied Solar Electric home that we discussed at the AIA in San Francisco a few weeks ago is unbelievably simple, reliable, and predictable. And it’s cost-effective today. No matter what our clients’ motivation is, whether it’s reducing carbon emissions, saving on energy bills, or reducing dependence on foreign oil, there’s an incentive for them to convert their home to GTSE,” Knight responded, and went on to urge the design community itself to take on the task of change.

“I think the AIA should take the lead in building and promoting Net-Zero Energy homes. I mean, a LEED certification can cost six figures and require what seems like thousands of meetings. By promoting Net-Zero Energy homes, the AIA could push their own agenda without waiting for the CEC to catch up.”

Why Can’t We Sell Back to the Grid?

What about people selling their excess power back to the utilities like they can in Germany? “There’s a difference between a feed-in tariff and selling back the excess through net metering. A feed-in tariff guarantees or fixes the rate at which power is sold back. Net metering simply measures how much energy is used versus replaced. But, any excess you produce is a gift to the utility,” said Gary Gerber.

“There are actually several bills that have come up for this in the past few years, including one that’s on the table right now. Allowing PV owners to sell excess would offer several benefits. For one thing, it promotes a cleaner environment because it uses no fossil fuels. But just as important is PV’s potential to reduce peak loads at the hottest times of the year, since peak cooling times are also when the sun is strongest.”

The Politics of Renewable Energy: Left and Right

Politically, there’s an unspoken divide between liberal and conservative approaches to power generation. Conservatives tend to push for nuclear power and offshore drilling, whereas liberals are more likely to promote clean solar energy and lifestyle changes. “We don’t care, it’s about what really works,” observes Green Compliance Plus founder Mark English. “Knee-jerk ideologies are not useful.”

There have been a few reported accidents, and safety is a major concern for both operation and waste disposal, but overall France seems to have a good nuclear energy model. A formerly oil-dependent nation, France invested heavily in nuclear power as a response to the 1973 oil crisis – now they actually EXPORT power. (Perhaps rather than dismissing it out of hand, we could seek to enforce accountability by requiring all nuclear executives and managers and their families to reside within a mile of their own power plants?)

Having said that, the ideological debate does tend to polarize along party lines. Solar power is viewed as an expensive boutique technology espoused by rich liberals like Al Gore who don’t always practice what they preach (remember when his Tennessee mansion turned out to have a huge carbon footprint, even after he wrote such reams on global warming? What were you thinking, Al?) It’s also possible that conservatives haven’t invested as much in renewables and thus don’t stand to profit from increased sales of renewable energy products and systems.

Who knows? When it comes to solar energy, I’d like to think that a chance to save money on energy bills and perhaps even make money as an entrepeneur, would be appealing to advocates of free enterprise. And, the opportunity for America to reduce dependence on foreign oil should appeal to political economists and xenophobes alike. What are we waiting for?