Electric and Hybrid Cars: The Saga Continues

Last time I was here I talked briefly about the history of electric and hybrid cars and their slow, but sure, emergence into the market over the past 20 years. With the global climate change debate reaching new heights and the push to be less dependent on oil, we have seen standards been implemented here in the U.S. and abroad for gas and diesel engine emissions. By 2025 we should be seeing a gradual increase in real-world fuel economy to about 45mpg for the average car and 32 mpg for the average truck. This is huge, considering I currently drive a 2011 V8 truck that does 18mpg on the highway. On a good day! But who doesn’t love V8 power?? Even with progress in engine and transmission technologies helping improve efficiencies across manufacturing fleets, we are here to talk about hybrid and electric cars, and how their steady progress will soon enough grab hold of the automotive world.

I mentioned on my last blog entry that we’re starting to see that racing categories (Formula 1 and the World Endurance Championship) have jumped on the hype-train regarding hybrid technologies and one racing category, Formula-E, has taken it a step further and is on its 3rd full season of an all-electric racing series. And the hype is definitely real! Mercedes Benz just recently announced that they are planning on pulling out of DMT (Deutsche Tourenwagen Masters), the NASCAR “equivalent” of stock car racing in Germany, to enter and focus its money in Formula-E for the 2019 season onwards. They are planning on battling it out with current manufacturers such as Audi, Jaguar, and Renault, who have already seen the racing series to be a proper investment. This will only lead to Electric Vehicle technology to take leaps in the next few years of competition alone.

This of course is driven by the push to get rid of as many emissions as possible. There have been talks of large city centers to ban diesel vehicles altogether by 2025; including Paris, Madrid, Mexico City and Athens. I previously mentioned that Ferrari is planning on having its full car lineup be hybrid cars by 2019 and Volvo has been the first manufacturer to formally announce that by 2019 it will only sell Evs and hybrid vehicles. Be prepared to see this technology further blow up in the next two decades, especially since two governments, Britain and France, have also formally announced to ban all gas and diesel car sales from 2040 and beyond.

It is definitely time to accept, even for us petrol-heads, that this technology is here to stay. There are new electric and hybrid vehicles popping up more and more, including pickup trucks and semis. Even retrofit powertrains are beginning to be installed in fleet vehicles such as FedEx delivery trucks and even garbage trucks, to put focus on large trucks that burn more fuel than standard passenger vehicles throughout the year. While it’s sad for purists to imagine a day when there might not be new, gas-burning cars to enjoy in the future, it’s good to see that we’re working on improving the world for generations to come.

- Victor Ceballos

Future ‘Buildings’ of America

The construction building process in all its aspects is a passion of mine –from the administrative side, Building Information Modeling, and the ever-growing selection of building materials that are now emerging and those that have yet to make their debut!  But what intrigues me the most about this process is the future of construction and where we have yet to go!  Oh, the possibilities!!!

Some common building materials that are making advances in their use and composition include concrete, metal, & paint…but there’s a whole different type of building material that is generating quite the buzz and even energy… glass!  And no.  I’m not talking about photovoltaic solar panels.  I’m referring to sheets of transparent glass or plastic film that can generate electricity! 

Ubiquitous Energy, a technology company originated at MIT, is responsible for the development of the world’s first truly transparent solar technology called “ClearView Power”!  This widely used building material could very well replace the way we live, design homes and buildings, and charge our electronic devices!

This amazing, new technology is a great alternative solution for generating free power from multiple surfaces!  According to Ubiquitous Energy, “ClearView Power technology can be applied to the display area of electronic products—including wearables, tablets, internet-of-things devices, and digital signage—generating electricity to power these devices.”

Researchers from Michigan State devised a unique technique for collecting daylight.  Previous attempts at creating completely translucent glass failed because some form of medium was always required to collect the sun’s rays- however- with the utilization of a Transparent Luminescent Solar Concentrator (TLSC)- they could discretely harvest the ultraviolet and infrared parts of the spectrum and guide it to the edge of the glazing where thin strips of conventional photovoltaic solar cells convert it into electricity!

The amount of electricity generated will not be enough to power your home or electronics indefinitely but with each Transparent Luminescent Solar Concentrator having an efficiency of 10%, every little bit counts!  When you think about a large, high rise building, there is a lot of vertical space to provide some free electricity!  Affordability is also a high priority of Ubiquitous Energy.  From small applications such as personal electronic devices to large, industrial and commercial construction, their goal is to provide this ClearView Power Technology at a low-cost to all!  (Just another reason to love this innovative building material!)

Overall, this alternative solution paired with solar panels could very well help to dramatically reduce dependence on other energy sources such as oil, gas, and coal.  Any step towards global renewable energy usage is a win/win to me!



Implementation of Commissioning and Monitoring as it Concerns LEED v4

The fundamental and enhanced commissioning credits in LEED v4 are similar to the credits in LEED 2009; however, the new requirements are more stringent and three additional points are available.  In addition, there are two new energy metering credits in the Energy and Atmosphere (EA) category in LEED v4, one is a prerequisite. These energy metering credits replaced the measurement and verification credit in LEED 2009. The LEED v4 commissioning and the monitoring credits are as follows:

·        Fundamental Commissioning and Verification - Prerequisite

·        Building-Level Energy Metering - Prerequisite

·        Enhanced Commissioning - Up to 6 points

·        Advanced Energy Metering – 1 point

The new fundamental commissioning and verification prerequisite has similar requirements to the old fundamental commissioning prerequisite, the main difference is the new required commissioning plan has more specificity.

The new enhanced commissioning credit has two parts, Option 1: Enhanced systems commissioning, and Option 2: Envelope commissioning.  Option 1 has two paths, path 1 has similar requirements to the 2009 enhanced commissioning credit, and will earn 3 points.  Path 2 is a monitoring based commissioning credit, and offers one additional point for including monitored system use and performance in an on-going commissioning plan. Finally, Option 2: Envelope commissioning (per ASHRAE 0-2005) can be added to either path from Option 1 for two additional points.

The building-level commissioning prerequisite essentially requires a commitment to share energy consumption data of the LEED certified building with USGBC for five years or until the building changes ownership.  This is also a Minimum Program Requirement (MPR) for LEED v4, and is required of all LEED projects. Monthly utility bills can be used for the energy consumption data.

Advanced energy metering requires that all individual energy end uses that represent 10% or more of the total annual consumption of the building must have sub-meters that are permanently installed, record data at intervals of one hour or less, and transmit data to a LAN, BAS, or comparable communication infrastructure capable of storing all meter data for a minimum of 36 months.

Therefore, installing sub-meters with logging capabilities along with increasing commissioning scope could potentially earn two additional LEED points. The real benefit of installing a continuously-monitored sub-meter system is the additional insight of the building’s continued performance, and the capability to fine-tune building performance in a holistic manner.

- Megan Mentillo

Company Spotlight: Rex and Vibrantcy

Rex and Vibrantcy

Why am I at Vibrantcy? After a full career in the consulting engineering business, why keep working? And, why work at Vibrantcy?

·       Because they asked.

·       Matt and Colin seem to find value in my experience and skills. Being in such an environment is a validation and a celebration of my career.

·       In the world of sports, lots of coaches … just keep on working. I can relate to that.

·       It feels good to still be engaged.

·       This is a special little firm. There is passion here. Passion for our clients. Passion for the work. Passion for the well-being of our staff.

Vibrantcy is unique. This firm has the potential to become very good. Matt Higgins has a highly-developed (and practical) talent for energy simulation work and energy-related commissioning challenges. Colin Evans has a passion for sustainable design and is an experienced and capable mechanical design engineer.

A word or two about “sustainable design”. I share with the staff at Vibrantcy a love for the physical environment and a desire to be a part of a sustainable future. I have been pro-environment my entire life. The first time I realized that I was a part of this minority was at a young age, probably about 10. I have been involved with pro-environment groups and activities throughout my life. It was not very popular 30 years ago to be a pro-environment engineer... there were not very many of us. Today, it is exciting to see the younger generation with a much greater commitment for a sustainable future. I am pleased about that and optimistic that good things will come from their leadership. At Vibrantcy, I see a sincere commitment to working for a sustainable future. I am impressed by the passion that lives here.

Rex history. Even though you didn’t ask, I’m going to tell you a bit about my personal history. Please check out if you are not interested. Perhaps one or two will continue reading.

My engineering career started in Cincinnati, at General Electric, designing jet engines. The obvious(?) next choice was, as you might guess, to work at Johns Hopkins University Applied Physics Lab in Washington D.C. There I worked on the Navy Polaris and Poseidon nuclear submarines, sometimes riding in the top of the sail with the captain. An interesting job, interacting with lots of intriguing people, many of them very impressive, indeed.

After that curious beginning, I decided to enter the crazy world of consulting engineering. And, more than 30 years later, after various roles ranging from design engineer to firm owner to university engineer to firm owner to design engineer, here I am at Vibrancy.

What am I doing at Vibrantcy?  I am gratified to be here … happy that the owners of this young company seem to appreciate that this old mechanical engineer may have something of value to bring to the table. At this point in my career, it feels good. It is validating.  

I’m like Allstate Insurance… I’ve “been there…seen that” regarding quite a few things in my career.

I occupy a unique position here, which is the token old guy. Just kidding, but, apparently, something about me has struck a chord with Matt and Colin. I strive to share some of what I have learned over the years. I strive to add value to this firm as it grows and prospers.

To that end, a part of my role here is to provide a bit of QA/QC for projects. And a bit of design. A bit of assist in several things. I hope to help keep them out of trouble. I hope to help them expand their visions. I want to help them to succeed.

It is refreshing and a new challenge to work with younger professionals who seem to place value on my experience and my contribution.

More history:

I’ve been blessed to be a part of some special design projects. Four come to mind.

·       The new Riley Hospital for Children at the IU Medical Center, an amazingly capable and compassionate place for very ill children, located in my hometown of Indianapolis, IN. My wife’s aunt, as a very young girl, was the fourth child to be admitted to original version of this wonderful hospital.

·       Master Facility Plan for Butler University Fieldhouse. This basketball cathedral, built in 1929, and considered to be one of the very finest places in the country to watch college basketball, has been a part of my life since I was 8 years old. I played basketball there in high school and was awestruck, like the boys from Hickory High in the movie “Hoosiers”.

·       The Birck Nanotechnology Center at Purdue University, a $56M research facility for multiple disciplines. As the University Engineer at Purdue, it was challenging and exciting to be working with so many very talented individuals on this very important state-of-the art research facility.

·       The GSA Land Port of Entry, a new $60M LEED Gold facility in Columbus, NM. My role was to be part of the review team representing the GSA. Again, the challenge and the stimulation was to work with all the many layers of federal agencies and design consultants assembled to design and build this new border facility.

I have basked in the glow of some great clients, like the longtime University Architect for Indiana University … who, when asked by another university to comment on my capabilities, said the following “he’s not any good, but he is better than everyone else”.

I’ve enjoyed some fun gigs in my career:

·       Riding on and working on Navy submarines was a highlight.

·       I feel most fortunate to have served for 6 years on the State of Indiana Commission for Fire Prevention and Building Safety, which is responsible for establishing and enforcing the building codes for the state. What a unique and fascinating experience. I learned so much, was a part of so many intriguing code issues, and got to work with so many different fascinating people. I loved the experience.

Wrapping it up: As you can surmise, I am making an effort to celebrate my career. I have been fortunate. But I’m not ready to pack it in. So, I’m also celebrating my present gig, which is the opportunity to work with this outstanding young firm named Vibrantcy.

Rex brief Bio: Please read on, at the risk of being swept over by a wave of boredom, and only if you feel you may want to know a bit more about my professional history.

Rex is a registered mechanical engineer with over 30 years of experience. His career has included successful roles in engineering and design, project management, staff management, client advocacy, and owner representation. His background includes extensive higher education and healthcare experience. He has excellent skills in planning, problem solving, and working on complex projects.

Rex has extensive technical expertise in large and complex HVAC systems, including building central air systems, chilled water and steam systems, automatic temperature controls, and mechanical codes. He has worked on dozens of projects that have incorporated sustainable features, including many LEED projects.

Rex's dedication to achieving desired outcomes is evident in his dedication to excellence. His projects are consistently responsive to the needs of the client. His projects have an excellent record of cost management.

Selected Significant Projects:

VA Hospital OR Expansion ($10M, 5-phase renovation), Albuquerque, NM

GSA Land Port of Entry ($60M LEED Gold), Columbus, NM, Review Team for GSA

GSA Montoya Building (100KSF), Santa Fe, NM, Master Facility Plan

PHS Lincoln County Memorial Hospital Master Facility Plan and Expansion Study (120KSF)

UNM Replacement Hospital Phase I (250KSF, LEED Silver), Albuquerque, NM

Commissioning of Indiana University, Multi-Discipline Sciences Building (LEED Silver)

Commissioning of Wishard New Replacement Hospital ($600M, 1.2 MSF, LEED Silver)

Cameron Community Memorial Hospital ($35M replacement critical access hospital)

Indiana University Jacobs Music Studio Building ($40M new LEED Gold building)

Utilities Master Plan for Indiana University and IUPUI main campuses

Mechatecture – The art and science of mechanical systems that make a positive impact on the architectural experience of a building.

Here at Vibrantcy we call ourselves “a mechatecture group”.  This simple combination of the words Mechanical + Architecture does not mean that we provide both mechanical and architectural design services, but that we strive to create mechanical solutions that are complimentary and integral to the architectural elements of a building.  We are a group of engineers and energy analysts who bring the same concept of character to building systems, as architects bring to the style and appearance of a building.  People interact with buildings using all five senses, so that the resulting experience is as much affected by temperature as it is by colors and textures.  We want to change the way that people interact with mechanical systems within a building, so that energy efficiency can be achieved while increasing the comfort, habitability, and maintainability of the building as a whole.  We can realize these goals by using the integrated design process, aesthetic design consideration for all typical building systems, and by implementing mechanized building elements.

Part of this concept of mechatecture is an extension of the Integrated Design Process (IDP), which is a holistic approach to high performance building design where collaboration between disciplines begins very early in the design process.  To move beyond typical building systems and successfully implement non-traditional methods of heating and cooling, the entire team needs to be on board while the design is still flexible.  All too often a building is completely designed before handing it over to the engineers to place the equipment and systems wherever they might fit.  The IDP has been adopted by the latest versions of LEED certifications in order to better identify design improvements that can be incorporated without adding significant cost to the project.  It can be thought of as the low-hanging fruit to avoid costly systems that may be needed to work around some building element that can no longer be adjusted late in the design.  A full explanation and commentary on the integrated design process is a good topic for another blog post (maybe even by a guest blog writer, any takers?).

The construction industry dictates that using custom materials will inevitably increase the cost of a project.  The success of most design architects depends on utilizing typical materials in a unique way to produce their desired design effect.  We have a limited number of different Lego building blocks to choose from, with the goal of making the product look like it was not built completely out of Legos.  Lighting fixture designers/suppliers have come a long way in offering unique solutions, but we still see so many of the same fixture type because they are the most affordable and produced in large quantities.  Uniquely successful lighting is often achieved by designing the ceilings or walls around a basic fixture to actually hide the fixture from view and allow the light to shine from an unusual cove or shaped ceiling.  This is adaptation of the building around a system, using conventional materials.  With HVAC systems I see less innovation in using ductwork or diffusers to enhance a design, but with thoughtful consideration we can learn to use the basic building blocks in unique ways and adapt the building around mechanical systems.  Can you spot the HVAC building block in the photo below on the left?


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    Photos By: Colin Evans   Location: Mayo Clinic in Scottsdale, AZ

Photos By: Colin Evans   Location: Mayo Clinic in Scottsdale, AZ

The third concept behind mechatecture is the realization that not all architectural solutions are static, and that in order for buildings to evolve to the next level of efficiency there will be an increase in building components that are actually mechanized and automated.  Traditionally, there are not many parts of a building that people can see that actually move.  Most examples of this would be considered artistic sculptures, which aren’t necessarily responding to or affecting the environment.  As part of the design process the team might identify a structure or building component that needs to move in order have the desired effect.  The most common example of this would be mechanized solar shading, which lets in sun and light when needed and deflects it another direction when unwanted.  This example is very much an architectural element that has energy efficiency advantages, requires a scientific approach to optimize its movements, and has moving parts to be designed, built, and maintained.  Whose scope does this fall under?  The most likely answer in this case is that the supplier of the product would take most of the responsibility. 

But what if the design team came up with a solution that was less common, or had never been done before?  A solution that utilizes standard materials and simple mechanics to achieve a unique result could easily fall through the cracks without a team willing to take full responsibility for something that is outside of the box.  The simple idea of natural ventilation relies on the coordinated movements of building elements in response to a multitude of sensors inside and outside of the building.  The components and controls are ordinary, but the sequence of operation are unique to the specific micro-climate of the building.

Here at Vibrantcy we are taking on buildings’ greatest challenges with passion.  We can’t expect to remain in the traditional role on a traditional team, and achieve high performance results.  We are educating ourselves about cutting edge techniques in order to share our knowledge with colleagues, clients, and staff about what we have learned about better living in our built environment.  Our buildings can become an extension of our natural environment only when we take the chance to learn from others, instead of depending on our own limited experience and staying within our comfort zone. 

Electric and hybrid cars – welcome to the new norm?

Ever since watching the documentary “Who Killed the Electric Car?” 1, I’ve been curious as to where the electric car industry would be at this point if the plug on the GM EV1, and other Electric Vehicles (EVs), hadn’t been pulled in the mid-1990s. Even so, hybrids have been popping up more frequently, and EVs – such as Teslas – have had a positive impact within the market, with a clear demand for them.

The film points to some conspiracy theories - which I’m inclined to believe - regarding the influence that oil companies and their lobbyists have on our government’s decision making; such as making it difficult to build public charging stations. On the other side, we had auto-makers worried that the new type of vehicle will reduce revenue in regards to things such as maintenance and tune-ups. In reality, the push for more efficient vehicles has been mandated by regulations imposed by government entities to reduce emitions, and any work towards that takes away from building cheaper cars to sell for higher profits, which is what car companies are about. Even with the attempt to halt the emergence of EVs two decades ago, from 2005-2014, there was an average of 352,306 hybrid vehicles sold, according to the USDT.2 And the future looks bright for both hybrids and EVs; in March of 2016, 325,000 people put down a $1,000 deposit for Tesla’s new Model 3, which won’t even reach their buyers until late 2017. While this doesn’t tell us that everyone is onboard to buy EVs, it points towards enthusiasm about the technology and the positive impact it may have.

Perhaps the biggest sign that hybrids and electric vehicles are here to stay is the fact that racing series have been adopting these technologies in the past few years. Formula 1 brought forward the hybrid era in 2014. The switch from naturally aspirated, 2.4L V8s, to turbocharged 1.6L V6s mated to multiple Energy Recovery Systems has brought forward an unprecedented increase in efficiency. These energy systems take wasted energy from the brakes and the turbo charger and power the 120kW electric motors that provide an additional jolt throughout the lap. Earlier this year, Andy Cowell, Managing Director of Mercedes AMG High Performance Powertrains, mentioned that these small, 1.6L V6s are producing over 900bhp and have an astounding thermal efficiency of 50%.3 By comparison, these new engines deliver more horsepower than 3.0L V10s from a forgone era, and make the 30% thermal efficiency of regular gasoline engines seem a bit outdated. We’re talking about an increase in efficiency of 66% in only three years of the new engine era, with more to come in the new era of engine regulations for 2017.

Another series making its way into the racing world is Formula E. While this series hasn’t really grabbed the attention of the masses, racing series are used by automakers to design and develop these new technologies and increase their impact on their road-going vehicles. These all-electric formula-style race cars are equipped with a 200kW engines, with a 28kWh Lithium-ion battery to last half of the race. Power limits have been increased in the coming years. Currently the drivers are required to use two cars to complete the race distance, meaning drivers switch cars halfway there. One of the goals is to get rid of the need to change cars. What makes this interesting is the fact that Ferrari CEO, Sergio Marchionne, recently mentioned that Ferrari is considering joining in the future when the series has matured and when it makes sense that the use of this all-electric technology will help to improve their road cars.4

While the hybrid and EV percentage in the automotive market is still very small, it is safe to say that the development of these technologies is here to stay, which will in turn make more consumers warm up to the idea. When you hear that Ferrari, the automaker known for making some of the world’s most famous and powerful naturally aspirated gasoline engines, is talking about having their full automotive lineup go hybrid by 20195, then that tells all petrol-heads that the shift is real. Not to mention the many hybrid supercars already on the market from the likes of Porsche, McLaren, and Audi.


1.     Who Killed the Electric Car?, Directed by Chris Paine, Sony Pictures Home Entertainment, 2006.

2.     “Table 1-19: Sales of Hybrid Vehicles in the United States”, United States Department of Transportation,


3.     “Fuel Thermal Efficiency”,


4.     “Ferrari outlines requirements for possible Formula E entry in future”, Autosport, http://www.autosport.com/news/report.php/id/127039

5.     “Marchionne Says All Ferraris Will Be Hybrid Starting in 2019”, Road & Track, http://www.roadandtrack.com/new-cars/future-cars/news/a31483/marchionne-ferrari-hybrid-2019/

Post-Occupancy Services are worth the Investment:

Vibrantcy’s post construction services comprise a significant portion of the company’s workload via one year post-occupancy retro-commissioning (RCx) and energy measurement and verification (M&V). The diagnostics required to perform these services vary based upon building type and systems complexity, however in all cases building automation system (BAS) trends are setup and heavily scrutinized.


When performing RCx services BAS data is evaluated against weather-data, design intent, energy consumption, base energy-loads, and peak energy demands. Correlations among these datasets are drawn based upon the usage patterns of facilities, giving our engineers the ability to recommend small operational changes and set-points to remain within design parameters. In many cases these post-occupancy services lead to improved thermal comfort and reduced HVAC run-time.


More specifically in recent projects for the Central NM Community College, RCx services were performed for 450,000 square-feet of facilities resulting in over 80 energy conservation measures. In a recent post-RCx implementation instance a central chiller was observed to operate 20% less than pre-RCx assessments, extending the useful life of the chiller plant and associated equipment.


Similarly, Vibrantcy’s M&V services have helped facility owners understand the value of capital investments one year post-occupancy. Using data very much like the RCx datasets, M&V requires detailed energy model calibration, using design-phase models to understand how a facility is truly operating. In most instances Vibrantcy’s design-phase energy models are within a 15-20% margin of accuracy, through calibration these models are much more accurate (within 5-10%). Using as-built drawings, submittals, ASIs, and other construction phase information calibrated models allow building owners to determine the replicability of design features for future projects.


In one recent instance measured and quantified documentation of before and after performance suggested an annual savings of $20,086 by choosing the building systems in a Colorado High School. Should the school have implemented other alternative systems than those chosen for construction, they may have saved an additional $13,087, as indicated by calibrated energy models.


Measurable energy savings are best determined when sub-meters are implemented as part of construction, and are accessible subsequent to occupancy. Diligent specifications are necessary in order to develop a useful monitoring and data-archival system, which can produce extremely useful performance data for inclusion in both RCx and M&V analysis. In some cases sub-hourly sub-meter can be used to populate calibrated energy models, which is helpful when performing guaranteed savings calculations through regression analysis.


In either case, RCx and M&V services help building owners and manager gain a deeper understanding of actual systems performance, often spurring small operational recommendations to save significant amounts of energy. We’ve recently completed our 43rd RCx analysis for PNM customers, and would love to share our findings with you!


Matthew Higgins, Founder & Chief Analyst


Can we cool our spaces without heating our planet?

Setting foot outside in Albuquerque any given day this summer has served as a constant reminder that each of the last 14 months has broken records as the hottest of its kind in history. Indeed, there is little doubt that 2016 will go down as the hottest year on record. However, perhaps the one positive piece of news associated with the atmosphere this year was the announcement that the hole in ozone layer over the Antarctic is finally beginning to heal. The Montreal Protocol worked.

Originally signed in 1987, the Montreal Protocol was the first global legislation to preserve the quality of Earth’s atmosphere. This agreement was signed by 197 countries in response to the discovery of the gaping hole created in the ozone layer caused primarily by chlorofluorocarbon (CFC) emissions. At the time, CFCs were the most widely used refrigerants with R-12 or Freon being the most well known one of these. The ozone layer is a most important part of the atmospheric construction because it reflects a great deal of UV-B radiation back into space. Without this protection, skin-cancer rates would soar, marine life would suffer, and crop yields would decrease. The protocol created a framework to phase out ozone-depleting chemicals beginning by banning CFCs.

Although the biggest culprit had been dealt with, CFCs are not the only halogen-containing refrigerants that contribute heavily to global warming. Hydrochlorofluorocarbons (HCFCs) were the cheapest alternative to CFCs, and had a lower ozone-depleting potential. The most common HCFC refrigerant is R-22, and although no new systems using R-22 have been manufactured in the US since 2010, it is still important enough for Wiley to include complete thermodynamic tables for the refrigerant in my Fundamentals of Engineering Thermodynamics textbook. R-22 will no longer be manufactured after 2020.

The hole in the ozone is healing and the most ozone-depleting chemicals have been banned and phased out, so why are the current refrigerants still under attack from environmentalists? The answer lies in the global warming potential (GWP) of these refrigerants. A GWP is assigned to a gas with carbon dioxide as the reference, and many commonly used refrigerants have GWPs in the triple and quadruple digits (i.e. If emitted, these gasses contribute to global warming hundreds to thousands times more intensely than carbon dioxide). For reference, R-22 has a GWP of 1810, R-134a has a global GWP of 1430, and highly used R-410A has a GWP of 2088. The latter two refrigerants are hydrofluorocarbons (HFCs), which are used in most commercial and residential air conditioning applications today.

Industry leaders, such as Emerson in a whitepaper published in 2014, claim that “one good option for air conditioning applications is to stay with HFC options such as R-410A until an economically viable alternative becomes available.”1 The justification for this is a metric called the Total Equivalent Warming Impact (TEWI) this takes into account not only direct emission of refrigerant, but the effects of system efficiency and source of electricity. Furthermore the total contribution of HFCs to global emissions is less than 3%.1 However, the bottom line is that it is more expensive and often more dangerous to create air conditioning systems using alternative refrigerants with similar efficiencies to those achieved with HFC refrigerants. It would appear that this excuse is losing effectiveness as the US is already proposing an amendment to phase down HFCs to 15% of baseline by the early 2030s. World climate leaders recently met in Vienna to discuss this next stage that could set the stage for a 2016 amendment to the Montreal Protocol.2

So where does the air conditioning industry proceed from here? Halogen-free refrigerants do exist. In fact, carbon dioxide (a.k.a. R-744) itself is one of the oldest refrigerants. A major hurdle in developing systems with CO2 as the refrigerant is the 30-50% efficiency hit incurred by using CO2 over HFCs in a simple thermodynamic cycle. However, CO2 does have favorable heat transfer coefficients and one effective way that systems can be designed with CO2 as the working fluid is to employ transcritical operation. CO2 does not condense at higher pressures like HFC refrigerants, so a gas cooler replaces the condenser in transcritical cycles. Initially as least, this thermodynamic cycle modification will require additional spending on R&D and a higher first cost of systems. Ammonia can also be used as a refrigerant and is attractive because it has no direct GWP. Unfortunately, ammonia’s toxicity makes it unsuitable for residential air conditioning applications. Finally, traditional hydrocarbons can be used as refrigerants, and at this point in history they are still cheap and abundant. However, their extreme flammability make them a tough sell to commercial operators.

Since 1987, the air conditioning industry has successfully continued to deal with regulations on their most common refrigerants while still improving efficiency. I commend the industry for innovating in system design rather than pushing back against regulations. It could be considered ironic, but it appears that the gas, which we have been pumping into the atmosphere since the industrial revolution thereby warming the planet, could soon be the standard working fluid coursing through thermodynamic cycles to provide cool air through our diffusers.

About the Author

                  Jeffrey Sward recently graduated from the University of New Mexico with a Bachelor of Science in Mechanical Engineering, and will continue his studies at Cornell University in the coming fall. As a New Mexico native, Jeffrey naturally enjoys the backpacking, fishing, snowboarding, skiing, running, and most other things outdoors, and he uses this as a justification for his interest in climate change and energy efficiency.


1 Refrigerants for Residential and Commercial Air Conditioning Applications. Tech. Emerson Climate Technologies, 2014. Electronic. http://www.emersonclimate.com/Documents/Resources/2007ECT-136.pdf

2 Ragendran, Rajan. Refrigerant and Energy Regulation Updates. Rep. Emerson Climate Technologies, 2015. Electronic. http://www.emersonclimate.com/en-us/About_Us/industry_stewardship/E360/Documents/Anaheim-Presentations/e360-anaheim-refrigerant-and-energy-regulations-update.pdf

3 Moniz, Ernest, and Gina McCarthy. "A "Cool" Way to Combat Climate Change under the Montreal Protocol." Energy.gov. US Department of Energy, 20 July 2016. Web. 21 July 2016.