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Net Zero and Electrification

Net zero” can mean a lot of different things depending on what you choose to measure – zero energy usage, zero carbon emitted, zero lifecycle impact, etc.

At Steven Winter Associates, Inc. (SWA), we work with clients who are approaching net zero from different angles: driven by institutional goals, climate concerns, marketing campaigns, and connecting with municipal emissions targets. One thing we see over and over is that super high performance is difficult to achieve, but with a key simplification – there are not many ways to do it. All roads may lead to Rome but the closer you get, the fewer roads there are to take.

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5 New Year’s Resolutions for a High-Performance Year

We took some common New Year resolutions and put our SWA spin on them. This year, make resolutions to improve the built environment in 2020!

 

  1. Go on a (Carbon) Diet – diets are difficult, but as with all things, moderation is key. Reducing operational carbon use with super-efficient buildings is only part of the equation. We also need to understand the full Life Cycle of carbon use including building materials and products. Fortunately tools such as EC3 are making these analyses easier to understand; and products, including lower carbon insulation options and lower carbon concrete, are becoming readily available.
  2. Quit Smoking – enforcing no smoking policies is one of the best strategies to improve the health of all building occupants. If you do allow smoking, make sure you develop a good fresh air strategy and compartmentalize your units with a good air barrier. And check out more of our strategies for healthy indoor environments.
  3. Save More Money – lighting provides a significant area for savings. Sure, LEDs are great, but efficient design also means considering lighting power density (LPD). High efficiency fixtures placed in high concentrations still use a lot of energy and can result in over-lit spaces, which drive up upfront and operating costs. Lower your bills and the harsh glare with a smart lighting design.
  4. Travel More – seek out hotels and restaurants that people of all abilities can navigate with ease. Access Earth is an app that tracks the accessibility of public spaces worldwide to help take the guesswork out of accessible accommodations in new locations.
  5. Learn a New Skill or Hobby – looking to expand your horizons? Check out SWA Careers and join our team of change-makers to help develop and implement innovative solutions to improve the built environment.

 

 

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Call to Action: Voting Open Until December 6th on the Changes Proposed to the 2021 IECC

ICYMI: The code change proposals for the 2021 IECC are open for voting by Governmental Member Voting Representatives (GMVR) from Monday, November 18th through Friday, December 6th, and your vote is instrumental in making buildings consume less energy! [Need a quick refresher on the code process? Check out our blog post here!]

Does your vote even matter?

Overall, there are not actually that many voters on a given proposal. In the energy proposals, last cycle, it ranged from about 200-400 voters per proposal, even though there were a total of 1,247 voters on the Group B codes, which includes the IECC.

IECC voting numbers

So a small handful of voters can entirely shape the future of the energy codes that dictate how energy efficient our buildings will be! If history repeats itself, while some online voters tend to align with the Committee, many online voters align their votes with those cast by their fellow ICC voters at the Public Comment Hearings. This happened 81% of the time in 2016. Unlike 2016, in this cycle all the electronic votes cast during the Public Comment Hearings will be rolled into the online vote tally (although those voters can still change their vote).

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Zero(ish) – Waste Living

In a world where everything seems to be packaged in two layers of plastic, where we are encouraged to constantly discard items to make room for new ones, and where social media drives our desire to consume the newest trends, it can seem impossible to reduce our waste. Living a zero-waste lifestyle seems almost too overwhelming. I find myself wondering, “How can I possibly reduce waste when industries target consumers to do the opposite?” and “Even if I do make changes in my own habits, is it enough to make a difference?

I struggle with the same paralyzing vastness that Jonathan Chapman mentions throughout his book Emotionally Durable Design. Paralyzing vastness describes the tendency to do nothing when a task seems too large to conquer, instead of taking smaller steps. In the past, the seemingly vast nature of zero-waste living discouraged me from doing anything beyond entry-level recycling, but I realized that minimizing my waste is something worth tackling. Therefore, I will be sharing some ideas for working towards a zero(ish)-waste lifestyle — because going from zero to one hundred, or in this case one hundred to zero can be scary — and I’ll include my experience implementing a few of the ideas myself.

WEEK ONE: Apartment Composting

In blogs and articles that speak on behalf of zero-waste living, the importance of sharing with others and asking for help getting started is most frequently emphasized. For example, my apartment complex does not offer any composting services, but the SWA office does (yay sharing!). For week one, I started composting and designated two small resealable containers — one for food waste, and another for paper towels — that are now living on my kitchen counter. I intended on utilizing these two bins throughout the week, and then bringing them to the office for a dump. If you have the ability to start your own compost bin, that’s great too.

While using paper towels throughout the week, I felt less bad about it knowing that they wouldn’t be going into the landfill, but I developed some questions: If I use the paper towel with cleaning supplies, can it be composted?… Is it worth collecting small bits of food waste when I could just eviscerate them in the garbage disposal?… Are garbage disposals bad for the environment and/or do they affect the energy utilized for wastewater treatment?

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Electric Cars: Are They Better for Your Pocket and the Climate Right NOW?

Last week, I read a blog post from Connecticut Fund for the Environment President Curt Johnson, and he reaffirmed what I already expected: my next car will likely be an electric vehicle (EV). I currently drive a Toyota Prius hybrid, but when I bought it in 2013, the price to purchase and to operate an EV did not work out, so I chose the Prius, which has very reliably achieved 50 mpg over the last six years.

As an engineer who admittedly knows nothing about cars, I feel like the information out there on EVs is either slightly biased (i.e., published by EV manufacturers) or not transparent enough with the math to convince me. So I set out to create a blog post that was unbiased and transparent. I liked this one from Tom Murphy, an associate professor of physics at the University of California, San Diego, so hopefully I’m making it a bit more user-friendly and applicable to your current/local situation.

I just wanted to know two simple things (and admit to ignoring a long list of other factors that influence the type of car most people will choose to drive):

Number 1: At what gas price is an EV cheaper to drive per mile?

Number 2: While EV tailpipe emissions are zero, is my local electric grid clean enough that it’s a good idea, right NOW? I know my next car will be electric, I just don’t know WHEN the grid will be clean enough that it’s better for the environment for me to switch.

When I began writing this article, I had no idea what the answers would be.

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Become a Carbon Hero with Five Easy Tactics

Before you can really dig deep into the advanced design concepts of embodied carbon analysis and whole building energy modeling, you must first perform some bare minimum prep work. An easy way to get the pre-schematic plan up on its legs quickly is to add qualitative performance measures to the architect’s program study or create an Owners Project Requirements (OPR) document. For this article, “qualitative performance measures” refer to the metrics that express embodied carbon, but can also include operational energy, water, and even healthy materials.

Integrated Design Process Image An integrated design process (IDP) anchors the architectural program to performance metrics such as carbon dioxide equivalents (CO2e), Energy Use Intensity (EUI), and zero Energy Performance Index (zEPI). So, by completing the IDP, you’re getting the basic tools to optimize embodied carbon and operational energy use in your design:

  1. Target the early phase of the project
  2. Prepare a Carbon Hotspot and Simple Box energy analysis to compare carbon sensitivity of different schemes not limited to wall and roof construction, massing, and solar exposure.
  3. Schedule a workshop with the design team and owner to discuss findings and recommendations.
  4. Establish performance targets such as total Carbon Dioxide equivalents as a basic program requirement.
  5. Choose a compliance pathway and verify design with Life Cycle Analysis and a Whole Building Energy model.

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Building Energy Performance Standards (BEPS) are Coming to D.C., Are You Ready?

In January of this year, the Clean Energy DC Omnibus Amendment Act of 2018 was signed into law, establishing minimum Building Energy Performance Standards (BEPS) for existing buildings. The law requires all private buildings over 50,000 square feet to benchmark energy use and demonstrate energy performance above a median baseline beginning January 1, 2021. If a building does not score above the median performance, it has five years to demonstrate improvement or face financial penalties.

While quite a few of the details on enforcement are still being worked out, the median scores will be based on 2019 building performance and there are actions you can take today to get ready for BEPS.

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Recent Developments in Off-Shore Wind Energy Production and Renewable Energy Storage

Image of off shore windmills

Block Island Wind Farm, courtesy of the US Department of Energy[1]

Overview

There have been several local and global developments recently with regards to off-shore wind turbines. Advancements in energy storage from both wind and solar energy, coupled with the increased rate of adoption of wind turbines could serve as a major step towards a more renewable-based energy grid and a more sustainable future.

Updates on Energy Production

First, let’s explore some recent news surrounding the adoption of off-shore wind turbines. On a global scale, Scotland’s Hywind project recently proved that technology developed for and by the oil drilling industry can be successfully applied to off-shore wind turbines.[2] The floating 30 MW wind farm, made up of five turbines off the Aberdeenshire coast, has been operational since October 2017. During a three-month period of stormy conditions from November 2018 to January 2019, the wind farm managed to continue energy production at 65% of their maximum capacity. Note that during this period, a North Atlantic hurricane produced swells up to 27 feet! Over the course of a year  “maximum capacity” is approximately 135 GWh of electricity- or enough to power 20,000 Scottish homes. To ensure that the turbines can withstand weather events on that scale, the floating turbines are ballasted by 5,000 tons of iron ore, and 1,323 tons of chain anchor it to the seafloor. This off-shore farm proves that wind turbines can be successfully deployed in deeper waters where it would be increasingly expensive to extend the physical structure of the turbine tower to the seafloor. Additionally, the US, UK, Ireland, Portugal, Spain, France, and South Korea all have started to piggyback off the success of the Hywind farm in various ways. For instance, South Korea partnered with the Equinor, the primary backer of Hywind, to conduct a feasibility study for a 200 MW farm that would be located off the coast of Ulsan.[3][4][5][6]

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Rapidly Changing Brooklyn Neighborhood Welcomes Affordable and Sustainable Housing Development

image of Livonia Apartments

Courtesy of MAP Architects

The Livonia Apartments is Phase II of an affordable sustainable housing development in the rapidly changing neighborhood of East New York, Brooklyn. Through a partnership with the NYC Department of Housing Preservation and Development (HPD) and the New York City Housing Development Corporation (HDC) and designed by Magnusson Architecture and Planning (MAP), BRP Companies and partners developed this mixed-use, four-building complex to provide 292 apartments of both affordable and supportive housing, including 10% of units specified for persons with disabilities and municipal employees. In addition, Livonia II provides 30,000 square feet of community and retail space for the neighborhood.

The size and density of The Livonia Apartments project represented an opportunity to set a higher benchmark in green design strategies. Mayor Bill di Blasio stated at the groundbreaking, “For decades these vacant lots have been a blight on this neighborhood. Today, we’re breaking ground on a project that will deliver the affordable housing, good local jobs and vital services this community needs. We believe in a city where every neighborhood rises together, and where we make investments that give more people a shot at a better life.” Although the development straddles the busy elevated L & 3 trains and the Livonia Ave. station, the buildings’ facades are angled to minimize the sound and rattle from the trains, while maximizing privacy and natural light.

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Solar PV – The Revolution Continues

By the end of 2050, solar energy is projected to be the world’s largest source of electricity. While utility-scale solar will comprise much of this capacity, there will also be significant growth in the commercial and residential sectors – particularly in cities.

On episode three of Buildings and Beyond, Kelly interviews SWA’s solar expert, Eric Wallace, to discuss the various factors affecting solar photovoltaic (PV) growth including changes in technology, policy, and financing. Tune in to learn about some of the barriers and opportunities that solar developers face in the height of a solar revolution.  (more…)

Designing Solar for High Density Areas

As seen in:

Humans have been trying to harness the power of the sun for millennia. The advent and popularization of photovoltaics in the latter half of the twentieth century made doing so accessible to the masses. Today, solar arrays are commonly seen adorning the roofs of suburban homes and “big-box” retailers, as well as on other landscapes including expansive solar farms and capped landfills. Until recently, the common thread amongst these locations has been the employment of open space. Solar applications have historically been reserved for use in areas of low-to-moderate building density.

By the end of 2050, solar energy is projected to be the world’s largest source of electricity. While utility-scale solar will comprise the majority of this capacity, there will also be significant growth in the commercial and residential sectors – particularly in cities. Industry influencers are increasingly focused on creating opportunities for solar applications in high-density areas, where much of the demand lies.

In their 2014 Technological Roadmaps for solar PV and solar thermal electricity (STE), the International Energy Agency (IEA) predicts Solar PV and STE to represent over 25% of global electricity generation by 2050In their 2014 Technological Roadmaps for solar PV and solar thermal electricity (STE), the International Energy Agency (IEA) predicts Solar PV and STE to represent over 25% of global electricity generation by 2050.

 

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Nanogrids: A Whole Building Approach to Distributed Energy Resources

Distributed Energy Resources

Distributed Energy Resources (DERs) are a growing part of the energy landscape in the United States, and they are becoming an ever more attractive opportunity for households, companies, and building owners to gain control of their own energy needs. By 2024, it is estimated that solar PV plus energy storage will represent a $14 billion industry [1]. These resources are installed on the customer side of the utility meter and include distributed generation, such as combined heat and power (CHP) and solar photovoltaics (PV); energy storage assets, such as batteries; energy efficiency and demand management; and building energy management software. When deployed correctly, DERs have the potential to reduce the carbon footprint of the electric grid, increase grid reliability and resiliency, and defer the need for costly upgrades to grid distribution and transmission infrastructure [3,4,7]. (more…)

Solar Photovoltaics and New York Energy Code

Industry Trends

Over the past decade, the story of solar photovoltaic (PV) power has been one of both accelerating deployment and consistent, significant reductions in cost. This success has been driven by increasingly advantageous economies of scale, and supported by incentives and initiatives at all levels of government.

Figure 1. Solar PV systems have seen a dramatic reduction in cost

In late 2015, the federal Investment Tax Credit [3], a primary financial incentive for solar PV systems, was extended at its current rate of 30% through 2019, despite a contentious environment in Washington. It is scheduled to be stepped down through 2022, after which the commercial credit will expire and the residential credit [7] will remain at 10% indefinitely.

The National Renewable Energy Laboratory’s annual solar benchmarking report [4] shows that over the past seven years, PV system costs have dropped 58.5% in the residential sector, 59.3% in the commercial sector, and 68.2% in the utility-scale sector. As a clear sign of the times, utility-scale solar achieved the U.S. Department of Energy (DOE) SunShot Initiative’s goal of $1.00/W early this year, three years ahead of schedule [9]. According to the U.S. Energy Information Agency (EIA) [8], these trends should continue, leading to solar power’s increasing presence as a key component of the national electrical generation mix. The EIA projects solar to be the fastest growing form of renewable energy, increasing by 44% by the end of 2018 for a total deployed capacity of 31 GW and accounting for 1.4% of utility-scale electricity generation.

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Connecticut Proposes Budget Cuts on Clean Energy Funding

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Written by Carmel Pratt, Sustainability Consultant

If you live in Connecticut and are as obsessed with energy-related news as we are, you’ve probably already heard about the proposed cuts (to the tune of ~$22 million) from the state’s Regional Greenhouse Gas Initiative (RGGI) clean energy program. RGGI is a nine-state agreement between CT, DL, ME, MD, MA, NH, NY, RI, & VT to cap and reduce power sector CO₂ emissions. In other words, the program is designed to be a set of guidelines for regulating, budgeting, and trading emissions from electric power plants in the cooperating states. This initiative is the first of its kind in the nation, being a mandatory (as set forth by each state’s program design) and market-based emissions reduction program. The nine states are currently in the process of gathering input from stakeholders and experts for the 2016 program review. (more…)

Can A House Be Too Tight?

 

The Importance of Mechanical Ventilation

During most presentations we give about air sealing and infiltration, like clockwork someone will ask, “but doesn’t the house need to breathe, aren’t we making buildings too tight?” This is a popular green building myth, but  people need to breathe, walls don’t. In fact buildings perform best when they’re air tight and we can temper, filter and regulate the amount of fresh air.

We know the symptoms of poor ventilation – odors, humidity issues, condensation on windows, high levels of chemical off-gassing and even elevated carbon monoxide levels. Some of these effects are immediately apparent to occupants (odors, window condensation) while others may be imperceptible (carbon monoxide). Indoor air quality is a comfort, health and safety concern. However, these problems aren’t necessarily symptoms of tight buildings and can occur in all types of construction, old and new, tight and leaky.

Natural Ventilation Doesn’t Work Anymore

In the past buildings were ventilated with outside air naturally when the wind blew and/or it was cold. If this natural ventilation (or what building professionals call air infiltration) ever worked it doesn’t anymore.

red barn image

“Did you grow up in a barn?” Most of us learned as children the importance of keeping outside air out during heating and cooling seasons. However natural ventilation through building cracks brings unintended moisture and temperature differences that can cause condensation.

 

Old buildings had no insulation or air sealing, so structural failures caused by condensation within a wall assembly rarely occurred. Building codes now require insulation and air sealing which helps lower our energy bills and keep us comfortable inside. But when infiltration happens in a wall full of insulation, condensation can occur on the cool side of the wall assembly, which over time can rot the framing and cause structural issues. This is why it’s critical to prevent air leaks and better understand the thermal boundary.

Americans spend more time in our homes than ever, almost 15 hours per day by some estimates, and humans give off a lot of moisture. While home we tend to keep the windows closed. We’re also seeing increasing amounts of Volatile Organic Compounds (VOCs) emitted from our paints, furniture and household products that are made with chemical compounds that we know little about. For example, solid-wood furniture does not offgass, but plywood, particle board and foam sure do. How much solid wood furniture do you have in your house? Taken together this means there is more moisture, odors and pollutants added to our homes each day than was the case 30 years ago. The EPA estimates indoor pollutants to be 2 to 5 times higher inside homes than outside.Because of all these indoor pollutants, we clearly need to bring fresh outdoor air into the house.

However, the unintentional natural ventilation air our buildings do get rarely comes directly from outside. In the best-case scenario it creeps in through the various cracks in the exterior walls and windows, but most often comes from the least desirable locations shown in the image below: crawlspaces, garages and attics. Leakage from those locations is certainly not “fresh” air. Do you want to breathe in hot dusty attic air, or damp air from your crawlspace? You just might be.

Image of infiltration

Natural ventilation is forced through infiltration points which are most often from the unhealthiest locations in homes

Moreover, unintentional natural ventilation (infiltration) is unreliable and poorly distributed. Infiltration is primarily driven by wind speed and the temperature difference between outdoors and indoors. These weather variables vary day-by-day and season-to-season. For instance, the chart below shows the average conditions for Lancaster, PA. Note the weather fluctuations throughout the year:

  • During summer wind speeds are almost 50% lower
  • The temperature difference is 6-8 times greater during winter

lancaster-weather-conditions chart

These erratic conditions cause the building to be over-ventilated half the time and under-ventilated the other half. Also, infiltration is poorly distributed throughout the house. A room with a couple exterior walls and leaky windows will get far more outside air than an interior kitchen or bathroom. Wind and temperature differences drive ‘natural ventilation’ in the form of infiltration in homes. However these factors are highly variable and unreliable.

To summarize the need for mechanical ventilation:

  • There are more pollutants in our homes than ever, requiring more ventilation air
  • Homes are better insulated and air sealed than they used to be
  • Much of the infiltration that does occur comes from undesirable locations
  • Even the portion of infiltration that can be considered “fresh air” varies sporadically based on weather conditions
  • Having air leaks in an insulated wall, attic or floor assembly can cause condensation and create structural failures.

For all these reasons, relying on air leaks as natural ventilation no longer works. It doesn’t work for normal homes, and it especially doesn’t work for insulated or tight homes.

Build It Tight, Ventilate It Right

The better approach is to provide controlled mechanical ventilation by providing enough air to meet ASHRAE 62.2 and air seal the house to prevent moisture issues, high energy bills, and air from the attic and crawlspace or basement from polluting our indoor air.  As the mantra goes, “build it tight, ventilate it right!”

A well-designed ventilation system brings several advantages.

  • It allows control over exactly how much fresh air is delivered and when.
  • You can adjust the amount of ventilation air if the occupancy changes (e.g. kids go off to college) or shut it down altogether while on vacation, or when windows are open.
  • It delivers a consistent amount of air year-round, no matter what the weather conditions.
  • It draws air directly from outside, so the air is guaranteed to be fresh.

The main disadvantage to mechanical ventilation is the cost to run the fan. There are many different types of systems, with widely varying costs. As the following case studies shows, this additional cost can be more than offset by the savings in reducing the uncontrolled infiltration.

Mechanical Ventilation Case Study

Consider the following single family detached home renovation project in Lancaster, Pennsylvania. Before renovation, the house had no mechanical ventilation, and much of the infiltration air came from the attic and basement, providing dirty air to the house. The house was leaky enough to meet ASHRAE 62.2 levels for natural ventilation. But with an infiltration rate of 1.1 air changes per hour, the house was replacing all its indoor air every hour, leading to huge heating bills.

During the renovation air sealing brought the infiltration down by 70% and mechanical ventilation was added to deliver the recommended ventilation rate, which in this case was 0.20 ACHn.

Looking at the annual utility bills, in the original house it cost almost $600 per year to heat the infiltration air. After air sealing this was cut to $217. Heating the ventilation air cost $174, and running the fan cost an additional $14 per year. Not only is the house now less drafty and more comfortable, the indoor air quality is substantially better AND the homeowner is saving $194 per year.

Not every case follows this same savings ratio. If the original house was  tighter to begin with there may not have been any theoretical savings. If the mechanical ventilation system were more efficient, there could be more savings.

But remember that mechanical ventilation puts the control in the hands of the occupant, not mother nature. If there seems to be too much ventilation, the occupant can dial it back. If there are indoor air concerns the occupant can increase the rate.

Designing an Effective Mechanical Ventilation System

There are several strategies for designing a good mechanical ventilation system, and there isn’t a one-size fits all approach for homes, multifamily buildings and commercial spaces. It’s important to keep occupants in mind and install the proper controls to make the system work for them. Everyday Green has helped MEPs and HVAC contractors select and size mechanical ventilation systems for all budgets and size buildings, homes and unit spaces. But one thing is clear: relying on air leaks to provide fresh air is no longer an effective strategy. Contact us today with your mechanical ventilation questions.

Andrea Foss

 

By Andrea Foss, Director,  Mid-Atlantic Sustainability Services