building a sustainable and resilient community

At Home With HEMS

Posted on | September 2, 2015 | No Comments

(Originally posted on January 10, 2012; this topic has evolved since and will be updated in subsequent blog posts)

Working in the energy efficiency industry means – much as it does in other industries – that I deal with a lot of acronyms on a daily basis.  One of my favorite subjects, in fact, is an acronym that is just starting to gain traction in the EE “lexicon”: HEMS, which stands for Home Energy Management (and/or Monitoring) Systems.  If you saw my blog post on the 2011 DOE Solar Decathlon, you know I am pretty enthusiastic about high-performance, energy efficient homes.  Well here’s the thing… I also happen to think that the smart, sustainable homes of tomorrow will probably have some sort of HEMS in them.


(Photo: a HEMS app on an iPad from the Solar Decathlon)

HEMS are defined as any hardware and/or software system that monitor and provide feedback about, and often the ability to control and manage, a home’s energy usage.  Monitoring devices for the home, such as the Kill-a-Watt, have been around for more than a decade, but those first technologies on the market can be considered analog, at best. The state of the art has advanced significantly in the past several years, and even more so since the large scale deployment of smart meters.  Basic HEMS like the TED (The Energy Detective) can give you an overall picture of energy usage; mid-priced HEMS often have smart thermostats (although probably none as buzz-worthy as the Nest Learning Thermostat); and more mature HEMS have been developed, which can give customers detailed information about every energy-using device in their home, offer the chance to change the thermostat or turn lights off when you’re away, and even allow consumers to manage the charging of their electric vehicles at a home charging station.


(Photo: these dots light up when you are using too much energy… they are a very basic HEMS)

The market for HEMS has gotten so robust, in fact, that at one point in 2011 there was thought to be in excess of 300 manufacturers and vendors with unique HEMS products, and GTM Research forecasted that the market for HEMS (which are also referred to as Home Area Networks, or HAN) would grow over 90% to $750 million by 2015.  As if to emphasize that point, 2011 was a big year for many major HEMS companies.  NV Energy picked home-control pioneer Control4 for its big customer dashboard deployment; start-up EnergyHub launched its software-as-a-service platform; and Tendril announced it would be in millions of homes soon… and then promptly opened up shop in Australia.

Propelled by this momentum and my own fascination with innovative ways to make homes more energy efficient, in late Spring 2011, I helped launch an employee pilot using several HEMS in order to see first-hand how these devices work and to simulate the customer experience, amongst other things.  The market for HEMS is truly an early emerging technology market and as such, it is still very dynamic; case in point, one coworker who had access to Google PowerMeter through their TED device lost it when Google announced it was killing the PowerMeter in September 2011.  But, we’ve made do and we’re still learning all sorts of things from these devices, and in turn, we’re helping our clients learn about them as well.

Long story short, HEMS are here to stay.  But don’t take my word for it!  Soon you’ll be able to walk into a Lowe’s or a Best Buy and see for yourself.


(Never too late for some) Lessons Learned from the 2011 DOE Solar Decathlon

Posted on | August 31, 2015 | No Comments

(Originally posted December 12, 2011)

There is a village, once every two years, where you can not only see, but take a tour of, 20 of the world’s most technologically advanced and energy efficient high-performance homes.  This village is not, as you might imagine, at Epcot Center (although who doesn’t love a spin through Spaceship Earth) or at the highly-publicized World’s Fairs.  This magical village appears on the National Mall in Washington, DC, for the US Department of Energy’s biennial Solar Decathlon.

Started in 2002, the Solar Decathlon was founded by the DOE to demonstrate the potential for solar energy to power single-family homes.  What it has evolved into, in the five competitions since then, is a showcase for innovation, ingenuity, and collaboration in the design, engineering, and development of high-performance homes.  Every Decathlon, up to 20 college-based teams are invited to design a house, transport it to the National Mall, and then build it in the “Solar Village”, where teams participate in 10 contests for up to 100 points each.  The team with the most points at the conclusion of the competition period wins the overall Decathlon.  Each of the teams took a unique approach to their home’s design, selecting theoretical clients and partnering with manufacturers and vendors to develop starkly different solutions to the challenge of creating a net-zero energy home on the Mall.  

So why does the Solar Decathlon matter to the residential energy efficiency industry?  First and foremost, because the teams are trying to design net-zero energy homes, it is much more cost-effective to design a house that is 90% more energy efficient than a typical home, and then only have to provide renewable energy for the other 10% of the home’s energy needs.  Also, because the teams need support in order to fund their home building, they often partner with manufacturers who have products that haven’t shown up in the mass market yet, giving the public a “sneak peek” at new technology.  Furthermore, several of the teams have made it a goal to show that high-performance homes can be attractive AND affordable, driving home the point that technology is available to the public.  Finally, Solar Decathlon houses are innovative in their use of home energy management and monitoring systems, showing that renewable systems can be integrated with advanced HVAC systems, appliances, and consumer electronics to make homes better and more livable.

I gave a webinar on this topic (in 2011), primarily to show that the homes of the future don’t just exist in our imagination… they have been built.  For those of us who work with residential energy efficiency, and who look forward to the day when our homes are as advanced as our smart phones, it is encouraging to visit the Solar Decathlon every two years and to see it as America’s “living laboratory” for the smart homes of tomorrow.


What is Building Science, Anyway?

Posted on | August 22, 2015 | No Comments

(Originally posted on December 1, 2011)

What is building science, anyway?

I get this a lot.

When I tell people that I’m a Technical Manager for Building Science, I’m usually met with confused looks and further inquisitions about what my job entails.  The words “building” and “scientist” are not exactly used together very often in practice, let alone in conversation.  Things get even more complicated when I explain that I have an architecture degree.  And when I’m talking to fellow architects, more blank stares… how exactly am I working with buildings but not designing them?

First, let’s cover the basics.

Building science, generally speaking, is the study of how buildings resist the environmental forces acting on them – everything from moisture protection, to solar gain, resistance to lateral forces from wind and seismic shifts, and how they use daylight.  It’s not just about a particular microclimate surrounding a building, however; it’s about that building itself, and how its envelope protects occupants from the elements, how its systems create interior thermal comfort, how it manages water and electricity demand, and how efficiently it does all of those things.

So I’ll admit, that’s a lot.

But I love buildings… Inspired by some of the greatest structures on Earth, I first went to architecture school to get a foundational knowledge of how to put buildings together, and how to do so thoughtfully and artfully.  And as it turns out, I love science too.  I actually enjoy talking about things like weather and soil properties and thermodynamics (nerd alert).  I am fascinated by new materials and technologies that could make our lives better and easier.  You put all of these things together, and you’ve got somebody who’s passionate about the systems that make our built environment work.  And so a self-proclaimed building scientist was born.

I’m joined in this field by other designers, engineers, energy professionals, and planners who recognize the challenges in creating a more sustainable built environment, and who also realize that traditional job descriptions may not fill our needs going forward.  In order to create more energy efficient, sustainable buildings, design teams need to work together from the beginning to make informed decisions about everything from the building’s shape and orientation to how it will get energy and where its materials will come from.  Architects, engineers, and contractors are learning more about aspects of the building process that were once unheard of, like recycling materials in construction.  These collaborative teams are responsible for many of the first sustainable buildings, and they’ve paved the way for more professionals to create the next generation of energy efficient and high-performance buildings.

So when people ask me what I do, I’ll usually get past the initial head-scratching that inevitably occurs with the “building science situation” by comparing my job to the ad campaign of the international manufacturing company 3M, “I don’t make buildings, I make buildings better.”  And that’s a pretty cool thing to do for a living, if you ask me.


1 month and 3 days

Posted on | August 19, 2015 | No Comments

When I first launched this website in 2009, I did so in conjunction with my graduate thesis, which I spent studying ways to encourage people to save energy. I did this because of global warming and because I believed that we could fight it. I set up the entire HTML page, and I put a counter on my blog: “We have X months and X days until we must start REDUCING our global greenhouse gas emissions, lest we will be destined for catastrophic climate change.”

Since I launched this site, I got a job. I rode by bike a few thousand miles, I climbed a mountain in Africa, I got a dog, and I bought a house. Basically, I got distracted by life. But in my job, we saved a lot of energy, so I felt confident that I was doing all that I could. Apparently it was still not enough. The counter on the blog post now says “We have 1 month and 3 days…”

I will be re-posting some (now deleted) blog posts that I wrote over the past several years that document my personal journey to this point, and eventually I will add some new thoughts as we approach that point of no return.


Solar Decathlon 2011!

Posted on | September 25, 2011 | No Comments

Greetings from Washington DC, where I am visiting the 2011 Solar Decathlon.  This year, the university teams have set up shop in West Potomac Park due to a conflict on the National Mall.  The new location is slightly more difficult to get to but the journey is worth it… there are so many amazing things to see in these houses!

I brought my camera and have taken lots of photos but I managed to leave the cord for downloading the photos at home.  Needless to say I will post pictures as soon as I return to Portland.  I have seen 12 of the 19 houses so far, and they have had some amazing features:

  • New Zealand’s “First Light” bach: an all western cedar holiday house with a refined, open interior
  • Parsons / Stevens Empowerhouse: a house built for Habitat for Humanity of DC
  • SCI-arc / CalTech’s CHIP: a house with blanket-like “outsulation”
  • Team Belgium’s E-Cube: a pre-fab house with an IKEA-style assembly manual
  • Team Canada’s TRTL: a tribal-inspired technological house
  • University of Maryland’s Watershed: a lush, water-efficient home (& the current competition leader)
  • Team Massachusetts’ 4D house: a spacious, livable home with a solar PV porch
  • Team New Jersey’s ENJOY: a chic pre-cast concrete home with modern touches
  • Team Florida’s Flexhouse: an open, airy home for Florida climates
  • FIU’s perFORMDance House: an ADA-accessible home with hurricane louvers & copper cabinetry
  • Tidewater Virginia’s Unit 6: a traditionally-styled, developer-ready home
  • Appalachian University’s Solar Homestead: a modern home built with modules around a central outdoor pavilion… probably my favorite so far

I will talk more about the particulars of these houses once I have absorbed them all (and then again when I have photos).  If you are in the area, these are definitely worth a trip!  If you are around, you can probably find me tweeting about what house I am visiting… come find me @theGDC with the hashtag #SD2011.


Living Building Challenge IRL

Posted on | May 23, 2011 | No Comments

Last week was our penultimate topic week in the Sustainable Buildings class, and it was an important one:  we covered the Living Building Challenge, one of the “deepest green” sustainable building standards in the world.  It was even more appropriate a topic when you consider that it was started in our own backyard in conjunction with the Cascadia Green Building Council, and originally conceived by Jason F. McLennan, CEO of Cascadia.  It is now administered by the International Living Future Institute (formerly the International Living Building Institute) and there are currently three buildings in North America that have achieved full “Living status”.

One of the most important things to keep in context within the framework of this class is, how does this standard relate to the other systems, standards, and methodologies we’ve seen?  Observe:

  • ENERGY STAR:  This government-sponsored system is used widely by building professionals and manufacturers.  But, it is somewhat unwieldy with lots of checklists and tools and has been rejected in multiple jurisdictions for being too complicated.
  • State programs and codes: There are too many of these to mention, and they range from prescriptive to performance, regulations to codes.  Standards vary from place to place and can be quite helpful in certain areas – if you know how to take advantage of them.
  • Architecture 2030:  This organization sets ambitious goals but provides very little framework for how to get there.
  • LEED:  This large and dense standard has achieved what we might call “market transformation” due to its position as THE green building benchmark.  But, to achieve certification you must wade through mounds of paperwork and fork out lots of money.
  • Passive House:  This simple and straightforward standard places a premium on high performance, but is perhaps not as comprehensive as some of the other systems.

In contrast, the Living Building Challenge asks the question, “what if every single act of design and construction made the world a better place?”.  With the LBC, the ideal outcome IS the goal, and there are no choices about whether or not you follow the “imperatives”.  If you are trying to reach Living status, you either “go big or go home”.

This brings me to our field trip last week, the last one of the quarter… we are so fortunate in Portland to live in a community that places such value on sustainable living.  We have not just one but THREE Living Buildings in the works in the city of Portland!   The Oregon Sustainability Center, when it is built, will likely be the greenest high-rise ever built and reassert Portland’s status as a global leader in the green design community.  The Key Delta Living Building in North Portland will be a phenomenal resource to its community once it is fully transformed from the gas station it used to be.  But, as great as those buildings will be, they are not built yet.

The Living Building that IS built, or I should say nearly finished, is the commons, a two-family home in SE Portland that is a labor of love for the brothers building it.  Sticking to the integrity of the Living Building Challenge has been a – dare I say – challenge for the owners, but they have come a long way and will have one of the greenest houses in the land when they are done.  We had a good time on this field trip, and even took a class picture!

In front of the commons –
At the back (south) side of the house
Class picture!

Passive House!

Posted on | May 11, 2011 | 2 Comments

In class this week our topic is one of my favorite things, the Passive House standard.  Started in Germany as “Passivhaus” roughly 20 years ago, and validated as a way to create buildings that use as much as 90% less energy than their code-built counterparts, this is a simple way of building more energy-efficient, sustainable structures.  The gist of the Passive House standard is to build airtight buildings, with lots of insulation, reduce thermal bridging, and then ventilate, ventilate, ventilate!  By building more airtight structures, we ensure that these buildings don’t lose as much heating or cooling energy through cracks or gaps in the walls… but we also must provide a ventilation system that brings in fresh air, to reduce the likelihood of mold growth and generally support human health.

In discussing the Passive House standard, we learned that there are probably as many as 25,000 Passive House structures all around the world, the majority of which are in Europe, and only a handful of which are in North America.  One of these buildings is the Smith House in Urbana, Illinois, the first Passive House built in the U.S. in 2003 by Katrin Klingenberg, who literally wrote the book on Passive House.  Another Passive House is the University of Illinois at Urbana-Champaign’s Solar Decathlon house from 2009, also known as the Gable Home.  This house came in second in the 2009 Decathlon to Team Germany, who won their second Decathlon in a row.  We took this opportunity to talk about the technology and building science on display at the Solar Decathlon, and how great an event this is for green home designers and enthusiasts alike.  You can see more photos and read about my thoughts from immediately after the last event here.

from the Solar Decathlon 2009

Finally we got to the issue of our field trip this week to the Everhart Passive House in SE Portland.  The Everhart family has put a lot of time and effort into the retrofit of their house into a Passive House, and they are extremely generous for opening their home to our class.  For Assignment #5, we’ll be modeling the Everhart home using the Recurve modeling tool. Students are encouraged to bring a tape measure and their sketchbooks, and to “divide and conquer” spaces in the home to find inputs for all the rooms in the most efficient way possible.  See you at 10:30 on Thursday morning!


Midterms in the Sustainable Buildings Class

Posted on | April 29, 2011 | 2 Comments

This past Tuesday, we all got to see for the first time what buildings the students are modeling for their Term Projects, the primary objective of which is to evaluate a building’s energy consumption using three different methodologies.   The students will then derive from this process a better understanding of that building’s interaction with its environment and come to some sort of decision about how “sustainable” that building is.  With 20 students in the class, using three different tools, and only 10 weeks to complete the projects, we had a lot to talk about.  Roughy 2/3 of the class is studying commercial buildings while the remainder are looking at residential structures.    Students are using many of the tools depicted on the “energy modeling scale” here, and a few that don’t make an appearance on the scale.  Nearly everyone ran into some complications with at least one of the tools, with the most common frustrations arising out of – by my unofficial count – eQUEST.  Still, eQUEST is an industry standard and a byproduct of DOE2, so it is good for new energy modelers to get their “hands dirty” with it, so to speak.

One of the most common questions I heard from the students during the midterms was, “What are your expectations for us to come up with the right answer?” To which I say, this project and this class are not so much about getting THE right answer THE first time around,  as it is about getting AN answer.  The purpose of the term project is in fact to come up with multiple answers and then compare them with historical data to see how that building stacks up.  Energy modeling tools are imperfect creations… no single entity has a lock on how to calculate the energy consumption of even the smallest home, let alone a large commercial building.  So often, to paint a more accurate picture of a building’s energy consumption, we use multiple tools and then parse out what worked and what didn’t work.  The good news is, working with multiple tools not only gives us results that we can compare, it also offers the students the opportunity to gain experience on programs they may have never had the chance to use before.

And so it came to pass that we had a mid-term review in an architecture school in which everyone was encouraged to keep experimenting and make mistakes! Which in eQUEST is very easy to do  🙂   I am really pleased so far with the class’s investment in this project and happy to see the gears turning in their heads, especially since so many engineers and other building professionals think that architects “don’t care” about the systems and the energy consumption of the buildings that they design.  Architects care, for sure, it’s just that often we aren’t given the means to understand and work with this information.  Hopefully this class is a small but serious step on the road to changing that.


Architecture 2030 and Net Zero Energy Buildings

Posted on | April 19, 2011 | No Comments

Today in class we talked about Architecture 2030, which is a private organization started by Edward Mazria to, in their words, “achieve a dramatic reduction in the climate-change-causing greenhouse gas (GHG) emissions of the Building Sector by changing the way buildings and developments are planned, designed and constructed.”  Architecture 2030 is effectively trying to change the way buildings are built for the better, just like the ENERGY STAR program and many of the state and local programs that we covered in the previous weeks.  However, the goals, strategy and the messaging are notably different.  Architecture 2030 focuses on greenhouse gas reduction as a result of energy savings, while many federal and state programs place more emphasis on reducing energy and ultimately, costs.

This discussion of greenhouse gas (GHG) emissions seemed like an appropriate time to talk about how they are calculated.  Many of the tools and programs we are looking at in this class focus on energy consumption, but very few give outputs for GHG emissions.  If someone wants to calculate these emissions, an understanding of how variable GHG emissions are is necessary.  Following is a chart that gives rough averages for pounds of CO2 for each unit of energy measurement.

We talked a lot about tools and online resources that can calculate the estimated PV load for a building, once the energy consumption has been calculated.  Students will likely find a lot of help in these tools for their Term Project requirements.

Finally we talked about the Field Trip, which is a tour on Thursday morning of the PECI offices at Portland’s very new First & Main building. Assignment #3 is to use the spreadsheet analysis tool to try to come up with “Level 1” outputs. Some inputs students will be able to find on their own throughout the space, but some will not be obvious and will be given at the time of the field trip.  This should also serve as a reminder that students wishing to receive input on their mid-terms from REAL energy modeling professionals will have a chance to do so during the field trip!



State and Local Programs and Codes, and Assignment #2

Posted on | April 13, 2011 | No Comments

In today’s lecture, we dialed down into discussing state and local programs and codes, after having discussed the breadth and reach of federal programs in last week’s class.  There are many, many programs across the country, and even more codes and variations on codes in each jurisdiction.  But, since we’re in Oregon, it’s fair to use what we have in this state as an example.

The Energy Trust of Oregon (ETO) is an organization funded by the public purpose charge of its 4 member Investor Owned Utilities (IOUs) – PGE, Pacific Power, NW Natural, and Cascade Natural Gas.  This means that if you live in Oregon in one or more of these utility territories, there is a small charge on your bill each month which goes to funding ETO.  This money, in turn, is used by ETO to achieve energy efficiency throughout these corresponding territories.  But why?  Primarily because energy efficiency is a resource, just like the energy itself… if we collectively save enough energy, that means we can postpone, or even avoid altogether, the building of a new power plant.

ETO runs many programs which serve nearly every imaginable building type.  Among them are the New Commercial Buildings Program and the New Homes Program.  Both of these use incentives to encourage (or entice, if you will) architects, builders, homeowners, realtors, and everyone else involved in the life of a building to build more efficiently.  The New Homes Program, in particular, uses a metric called the Energy Performance Score (EPS) to describe the energy consumption, costs, and carbon emissions of a home.  This is much like the benchmarking, or “labeling” for homes that we discussed in last week’s class.  The EPS looks like this:

We then talked about codes, which – let’s be honest – are the LEAST bad that you can do.  They are a minimum standard and as such, when you are talking about designing a sustainable building, you probably want to work harder than code.  The good news is, there are now real codes for green building.  For energy, there is the IECC, while for green construction, there is the IGCC (supported by the AIA, ASHRAE, ASTM, USGBC, IES, and others).  In California, always ahead of the game, there is Title 24 and the recently adopted CALGREEN code.

All of this talk about state and local green building leads to our field trip this Thursday, which will be at 10:30 am the EcoFlats, 3951 N Williams, Portland, OR  97227.  The EcoFlats built a sustainable new multi-family complex in North Portland in part with guidance and incentives from the Energy Trust.  Assignment #2, then, is for the students to use the EcoFlats building as a “prototype” to do an energy model in either eQUEST or SketchUp with the EnergyPlus OpenStudio plug-in. eQUEST and EnergyPlus are both Department of Energy supported energy simulators, and it’s important that the students get some experience in one of these industry standards.

THEN we tried to do a demonstration of the EnergyPlus OpenStudio plug-in for SketchUp.  This did not go as planned, possibly because the program is buggy on Macs, or just because it is clumsy to begin with.  In lieu of the difficulty we encountered trying to get this plug-in to work, students who are able to actually get outputs from an energy model created with OpenStudio may get a “special prize” in next week’s class, if they can show us their work.  Students who ran an eQUEST model and want to show us their work may also get a “special prize”.

Happy energy modeling!  :o)

keep looking »