A Climate Action Turning Point!

That's friend of PHIUS and visionary NYC architect Chris Benedict (l) with Katrin Klingenberg.

That’s friend of PHIUS and visionary NYC architect Chris Benedict (l) with Katrin Klingenberg.

On October 29th I was fortunate to attend the NYSERDA low carbon and zero energy Buildings of Excellence Awards at the Building Energy Exchange in New York City. What a terrific time for projects that are about to and that have employed PHIUS+ passive building standards as baseline to get to zero energy ready! I counted at least 10 PHIUS+ project teams in NYSERDA’s three categories, Early Design Stage, Substantial Completion and Completed, that were awarded up to 1 million dollars for their projects!The awards were announced on the 7th anniversary of super storm Sandy, not a coincidence, as a reminder for urgent climate action. Seven years later, NYC is leading by action and is putting itself firmly on the path of global leadership in building energy and resilience. Thank you to an amazingly dedicated NYSERDA team for making this happen!

The week before the event, I keynoted the Boston Passive House Massachusetts Symposium to talk about the evolution of the PHIUS+ certification suite for passive buildings, and why they provide such great value on the path to ZERO. Here as well, political action was taken to combat climate change: MassSave staff announced significant incentives for low carbon and zero energy buildings and significant additional incentives if project teams go for passive building certification for their hi-rise residential projects. Certification requests from Mass have increased manifold as a result. Massachusetts in not far behind NY State in political will, turns out.

And just a few weeks before the Boston event, it was gratifying to find that at the Getting to Zero Forum in Oakland, California, passive building was simply understood as the logical starting point on the path to ZERO, no questions asked. During one of the plenaries the ASHRAE speaker proudly introduced the new ASHRAE standards committee: 227p Passive Building Design Standard. That was great news and evidence that ASHRAE is moving on the topic.

During the lunch plenary on day one the National Renewable Energy Laboratory featured PHIUS board member Mary Rogero’s students presenting their Solar Decathlon winning PHIUS+ Source Zero energy school design. For the closing plenary, California’s Commissioner Andrew McAllister presented on his recently completed and only recently occupied zero energy passive house in Berkeley and the benefit of energy independence. He had electricity while PG&E had shut off power supply to prevent fires, a consequence of climate change, to most of Berkeley including the entire Berkeley Campus. He was followed by Greg Hale, from NYSERDA, who spoke about applying the Energiesprong passive plus zero energy retrofit approach that he is spearheading in NYS and other zero carbon measures taken by the city.

And while most of the building action seems to be happening on the East Coast, quietly behind the scenes advocates have been working hard to get passive building into codes all over the country. When PHIUS was first established our lofty mission was to make passive building code by 2020. As ambitious a goal that was then in 2007, we have made significant progress toward it, and have paved the path for national success. NY State has included passive building as an alternative compliance path into the next stretch code and Washington State is on a similar path. Massachusetts has included an alternative compliance path for passive buildings and verification tools (no double modeling required) and Washington, D.C. also has included an alternate compliance path for passive buildings in their about to be launched ZERO Energy Code.

Most significant of all those developments is the establishment of the ASHRAE 227p standards committee. If successful they’ll created a passive building design standard that takes the best pathways from all existing programs and develop an even better, easily adopted design standard globally. That committee has now started its so very important work. The ball is rolling! Stay tuned for more!

Exciting times, indeed!

 

 

 

 

WUFI® Passive V.3.2.0.1 validation using ANSI/ASHRAE Standard 140-2017

Good news: PHIUS has completed modeling to validate WUFI Passive according to ASHRAE 140. Read the full report here

ASHRAE 140 is a comprehensive Standard Method of Test (SMOT) for the evaluation of building energy analysis computer programs. The ASHRAE 140 report provides the information accrediting agencies or jurisdictions need for validation or acceptance of WUFI ® Passive for code and policy purposes. In short, the standard describes test buildings (cases) in significant detail in order to model the building and compare results versus other software. It contains a comprehensive description of test procedures, as well as predictions generated by WUFI Passive software evaluated against predictive benchmarks.

The table below provides a description of the test cases used for ASHRAE 140 Validation. 

Table 1

Annual Heating and Annual Cooling Load results were reported for most cases, except for L302-L324A which only analyzed heating. WUFI Passive results fell well into the suggested acceptance ranges in all test cases when following Class II Procedures of ASHRAE Standard 140.  Most results fell toward the center of the confidence range as shown in the graphs below.
AHL Results

ACL Results

Authors: Lisa White, Jasmine Garland

 

A mid-cycle tweak of PHIUS+ 2018

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Space conditioning targets have been adjusted to reflect a statistical ‘Inclusive Fit’ rather than ‘Best Fit.’

PHIUS officially launched the PHIUS+ 2018 Passive Building Standard just over a year ago at the 13th Annual North American Passive House Conference in Boston. The passive building market seems to approve: not only have we gotten a lot of positive feedback from CPHCs and other design professionals, but PHIUS+ Certifications continue to increase. The most notable upgrades from the PHIUS+ 2015 standard add nuance to the space conditioning targets, adjusting them for building size and occupant density – passive building professionals do seem to appreciate this.  Another notable upgrade provides tiered source-energy targets and methods to hit those targets, depending on project goals.

Through the end of September 2019, PHIUS certification staff had the discretion to grant an exception for one of the four main space conditioning target criteria, as outlined in PHIUS+ 2018 Passive Building Standard-Setting Documentation, page 6. This allowance gave teams with projects already in planning some assurance that their efforts would not be wasted if their designs could not be revised to meet the new targets.  If a project was severely constrained on meeting a target, a “mulligan” could be granted based on majority vote from the certification staff. This also allowed flexibility in case the targets didn’t pan out in the real world even for clean-sheet designs.

Read the Full, Detailed Tech Corner Article

This “3 out of 4 ain’t bad” provision has now come to an end, and we have learned a lot from the many projects that have gone through the process. These case studies have allowed us to complete a mid-cycle evaluation of the standard. Determining optimum performance targets is an iterative process, and gathering feedback for future improvements is part of it. Thank you to all the teams that have certified to PHIUS+ 2018 helping us to dial in these improvements.

Moving forward, space conditioning targets have been adjusted to reflect a slightly different statistical fit from the original space conditioning target-setting process — an ‘Inclusive Fit’ rather than ‘Best Fit’ line. These updates will not disqualify any previously submitted projects in the PHIUS+ 2018 Certification process, as they are more inclusive than before. One sample graph of this is shown for the Peak Heating Load.

The Space Conditioning Criteria Calculator has been updated.

The Space Conditioning Criteria Calculator has been updated.

The resulting updated targets will be:

Cooling Demand = Original Target + 2.81 kBTU/ft2yr 

Heating Load = Original Target + 0.77 BTU/ft2hr

Cooling Load = Original Target + 0.45 BTU/ft2hr

The PHIUS+ 2018 Space Conditioning Criteria Calculator v2 has been updated to reflect the updates. Note the ‘v2’ at the end of the naming convention. 

Note

  • Projects with a contract date before October 1, 2019 may utilize only one path, (1) Use the updated calculator ‘v2’ or (2) Meet 3 of 4 space conditioning targets as described above.
  • Projects with a contract date after October 1, 2019 may only use the updated v2 calculator.

More details on this, as well as the graphs supporting the statistical analysis can be found in this Tech Corner Article

 

PHIUS+ 2018 Webinar Q&A

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PHIUS Senior Scientist Graham Wright and Certification Manager Lisa White answer questions that were submitted during and after the live PHIUS+ 2018 Webinar on November 8, 2018.

You can view a recording of the webinar at the PHIUS.org site.

*Note: Some questions have been edited for publication

Q: Has PHIUS started to look at overall GWP in the materials used to make these high performance buildings? To save the balance of the climate, reducing our emissions in the next 20 years is critical. Lots of XPS and spray foam make a low energy building but don’t do anything to help our climate goals.

A: The short answer is yes. We do have a GWP impact calculator for insulation. Its use is not required for project certification but we encourage it when we see large areas of XPS or SPF proposed. Our product certification program for construction systems has a requirement for a sustainability or health certification; there are several options recognized.

Q: Can you explain the exuberance concept?

A: We remain enthusiastic about the “tiny heating system” / “tiny heating bill” idea.

Q: Thanks for including Quebec Province! I believe in 2015+, all of North America was calculated according to a blanket value for cleanliness of the grid. Is 2018 adapted to different grids, and how do you deal with Quebec’s very cheap and clean hydroelectricity? Renewables are a tough sell here. Zero government incentives and at 7 cents/kWh, our energy costs would have to more than treble in order to make PV make financial sense.

A: In the standard-setting study itself we used the same factor all the time, but because the buildings were (almost) all electric, it canceled out. The PV generation is multiplied by the same factor as the usage, so source net zero is achieved with the same size PV array as for site net zero.

The philosophy is that CO2 emissions anywhere affect everyone everywhere. We all share one atmosphere, so by a principle of solidarity we should really use the world average source energy factor for electricity. That is, people with clean grids do not get to play “we’ve got ours” and use more energy. Even if your local grid is clean we want to drive additional action such as REC purchases that fund new clean energy projects. In certification we do allow the use of national averages, so we actually just request solidarity at the national level. Canada has a cleaner grid than the US overall, and thus Canadian projects will not have to take as many measures for net source energy reduction. The source energy factor for electricity in Canada is 1.96, whereas it is 2.8 for the US.

The electricity cost does affect some of the space conditioning criteria because higher energy prices justify more conservation measures and thus tighter targets. We calculate this with state-by-state averages, so Quebec projects will have less stringent targets than neighbors in Maine and Vermont.

 

Q: The word “townhouse” usually means a single-family building, but you seem to be using it differently.

A: The individual dwelling units are “single-family, attached”. That is, they share walls but not floor/ceiling. Speaking loosely, the whole row of attached units is the Townhouse, and the study building is 8 or 16 attached units.

Q: Is the mandatory minimum for window upgrades done because it wouldn’t be cost effective otherwise?

A: Yes. Window costs have come down but this still had to be forced in most cases. The starting points were still “in the money” though. There were a few times when the optimizer bought them on its own, but it took a long heating season and high energy price to motivate it. 

 

Q: Is this modeled EUI directly from WUFI Passive in the “Modeled vs. Measured” slide?

A: Yes, the WUFI Passive energy model used for certification.

Q: Do the new non-residential commissioning requirements apply to the common areas of residential buildings or only to all non-residential buildings?

A: TBD. Our current definition (for source energy target purposes) hinges on whether the spaces serve outside clients / customers or just the residents.

 

Q: Are you considering using the last 5 years of climate data vs ASHRAE to deal with global weirdness?

A: No, but we are working on future climate data for 2090 as an informational resource.

 

Q: Any comments on using low-iron glass (easily found in EU / just starting to appear in US)? Does the visible transmittance increase relative to ordinary US glass (which has a green tint to natural light)?

A: Alpen for a while had a low-iron glass option in their certified products, but they discontinued it.

 

Q: Instead of ignoring PV in competing with efficiency measures, why not look at PV with storage for the costs? This may not take care of seasonal differences, but it would take care of daily or weekly changes.

A: We may have have explored it if that was an option in BEopt, but it isn’t yet. Our current thinking is that what batteries do for you depends, in normal operation, on what the time-of-use rate structure looks like, and they are also good for you in outage situations. We are working on a calculation protocol for outages and waiting for utilities or other researchers to converge on time-of-use rate structure(s).

 

Q: Is there an ASHRAE 55 comfort analysis or PMV for PHIUS+?

A: The new window comfort calculator is based on relatively recent research on Predicted Percentage Dissatisfied specifically for draft at the ankle – it doesn’t just hark back to the PMV/PPD that was determined in 1970.

I (Graham) also wrote a paper for the 2016 conference looking at the radiant temperature effect of windows on comfort.

In certification we mostly take the same kind of simple view as in building code, e.g., “thou shalt maintain a dry bulb temperature set point of X and Y”. Sophisticated comfort analyses are more appropriate for workplace and nonresidential cases where clothing and metabolic profiles of occupants can be pinned down (as required by ASHRAE 55), and one might not have to worry so much about frail or sensitive occupants.

 

Comment: Adaptation is why I pursued CPHC in the first place!

Graham Wright: Thanks! Lisa presented on passive survivability at the Boston conference, and we will have more to say about this in the future.

Q: How does the new standard accommodate variable occupancy patterns/equipment usage in non-residential buildings?

A: With respect to the performance targets, as a first step, we will allow two different occupancies to be used to determine the annual demand targets vs. peak loads. Also, we can develop custom criteria for unusual situations (additional fee applies).

With respect to energy modeling protocol, it is already required to enter patterns for occupancy, ventilation and lighting, but this is mostly about getting the annual total energy right for source energy limit purposes.

 

Q: Please define HDD65, IGA, CDD50, TCD, IGCL and DDHR.

A: HDD65 = Heating degree-days, base 65 F;

IGA = Solar Irradiance, global, annual;

CDD50 = Cooling degree-days, base 50 F;

TCD = Temperature, cooling design day;

IGCL = Irradiance, global, cooling load design condition;

DDHR = Dehumidification design humidity ratio.

 

Q: If a project is considering registering under either 2015 or 2018, can we register under 2015 then change to 2018 (as circumstances change) without an additional registration fee?

A: Yes, you can always pursue a newer version of the standard. You are not able to pursue older versions if the contract date is later than the last day to submit under that older standard. In order to register for PHIUS+ 2015, the contract must be submitted before April 1, 2019.

 

Q: Are there updates to WUFI to accommodate the 2018+ standard? And when will it be available?

A: Yes, the next version of WUFI Passive will be released by the end of 2018. We will notify all of PHIUS’ mailing list.

 

 

 

 

 

 

 

 

PHIUS Travels to Shanghai to Keynote Passive House Alliance China’s 3rd Passive Building Summit

Katrin Klingenberg, PHIUS Executive Director

Developing Partnerships and Fostering Collaboration to Bring Climate-Specific Passive Building Standards to China

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The 3rd China Passive Building Summit took place in Shanghai Oct. 27-28, 2016.

This year I was invited to give the keynote address at Passive House Alliance China’s 3rd China Passive Building Summit in Shanghai, with the explicit request to report on passive building progress in the US and on PHIUS’ climate-specific standards.

In light of the immense amount of development currently taking place in China, with whole cities springing up practically overnight and a huge stock of existing buildings in need of energy efficiency upgrades, China’s interest in the passive building work being done in the US is significant.

It is expected that by 2030, a large amount of buildings will be newly constructed or retrofitted worldwide that will be equivalent to about 60% of the building stock that currently exists today worldwide. Thus it is crucial that these buildings, whether they be new construction or retrofits, perform at very high levels, ideally at zero energy or zero carbon performance thresholds, in order to tackle the challenges of global climate change. A large portion of this new construction activity will occur in China and India.

As I arrived in Shanghai a few weeks ago, my first impression on the way into downtown was “Wow, this is a really big place.” In fact, it is the largest “city proper” in the world. Shanghai consists of a conglomeration of countless high-rise residential subdivisions that emerge soon after leaving the airport and continue to expand along the hour-long ride into downtown. The implications of building on this scale came into focus again later that evening as I was at the hotel battling the jetlag of an 11-hour time difference following a 14-hour flight, when I heard the breaking news: the UN had just announced that 2016 is the first year on record that CO2 levels in the atmosphere not only hit 400 ppm, but that those levels have been sustained on average throughout the entire year. Needless to say, this is a threshold with serious consequences that will take a long time to reverse, and as you know, much of that CO2 comes from operating buildings.

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A recent study prepared by the Global Building Performance Network (GBPN) in Paris investigated passive buildings worldwide as a necessary solution to the climate challenge. For more information about the GBPN studies, you may view the reports at http://www.gbpn.org/reports

China is a big country, approximately the geographic size of the US, and has a significant diversity of climates, many of them very similar to the US. As such, and with well over 4 times the population of the US, the country’s building community shows great interest in PHIUS’ climate-specific passive building standards. A recent study prepared by the Global Building Performance Network (GBPN) in Paris investigated low-load high-performance buildings (ie. passive buildings) worldwide as a necessary solution to the climate challenge. For this study the GBPN developed a low-load space conditioning needs map (see image at right) which shows that the low-load systems profile (different combinations of heating, cooling and dehumidification requirements depending on climate) of the US looks almost identical to China. With such close similarities between the climates of the US and China, the implementation of our methodology for developing climate-specific passive building standards in China is a logical next step.

The 3rd Passive Building Summit was well organized and well attended, bringing in about 500 participants and a host of great presentations during the opening plenary followed by excellent technical sessions. On the day following my keynote, I participated in a technical workshop to assess how to facilitate continued collaboration between PHIUS and the Passive House Alliance China group going forward. We agreed that the applicability of the climate-specific passive building standards adapted from the US to the Chinese context is a no-brainer, however more work will still need to be done, such as developing metrics to incorporate local cost data for the best cost-optimized results.

We concluded the workshop with the Chinese passive building group in agreement to pursue further collaboration going forward and that PHIUS’ role in that collaboration would be to help generate Chinese climate-specific passive building standards using the same methodology used for the DOE/NREL report. In this arrangement, our Chinese partners would provide all the necessary information and parameters needed to run the calculations. As a first step on this front we have already generated the climate data set for Guangzhou for the first project enrolled for PHIUS+ 2015 certification.

Please stay tuned for more information on further developments with this promising new partnership as we look forward to tackling the challenges of climate change together.

 

– Katrin