Fred Hutch Research Reports Earning $20K Rebate with Stirling Freezers

In my last blog post, I highlighted how electric utilities and Stirling Ultracold customers are increasingly benefiting from rebates tied to replacing their legacy, compressor-based models with energy-efficient SU780UE ultra-low freezers. In this post, I’m happy to commend one world-renowned research institution who has reported earning rebates for their Stirling freezer replacement program.

In their newsletter “Hutch News”, Fred Hutchinson Cancer Research Center recently posted Ultra-low freezers earn cool $20K rebate from Seattle City Light. The second newsletter article reports how Fred Hutchinson (Fred Hutch) began the process of replacing its fleet of conventional compressor-driven ULT freezers with Stirling models in 2013. As a result, the facilities team was able to contract with their local electric utility, Seattle City Light, to receive rebates of $600 per new freezer. The Fred Hutch team has calculated that replacing their current freezers with Stirling units can save them 481,664 kilowatt hours per year, which equates to a savings of $27,937 annually in electricity alone.

In this newsletter post, Critical-Systems Supervisor, James Mead states . . .

“We did some operational and energy-use studies over a six-month period and were shocked because the energy consumption was so much lower compared to what we were using. Our studies found all claims by the company to be true, if not conservative. We were sold on it.”

Fred Hutch’s Material Director, Mark Burch, also commented, “To me, this is a great example of what happens when we all work together to support the science and save the environment.”

I’m thrilled to see another example of how our products are having a positive financial and sustainable impact . . . and how our users are just as thrilled to talk about it to their communities and stakeholders.

It’s possible that your research organization could also benefit from a utility rebate program for ULT freezer replacement with Stirling Ultracold models. Contact your Stirling Ultracold representative who can help with setting up the rebate process.

Stirling Users Increasingly Rewarded with Energy Rebates and Incentives

Plug and SparksAs the significant energy savings made possible by Stirling Ultracold freezers are now universally confirmed through independent testing and EPA ENERGY STAR® Final Test Method results, it’s not surprising that several major U.S. electric utility companies are offering rebates to research organizations who adopt our ULT freezers.  Many sustainability-conscious research institutions are also now incentivizing the purchase of our freezers by offering their own internal rebate programs.

Below is the growing list of utilities and research organizations that have implemented ULT energy rebate/incentive programs for buying our freezers so far . . .

  • Duke University
  • Eversource Energy (formerly NStar) rebate for:
    • Harvard University Faculty of Arts & Sciences
  • Pacific Gas and Electric Company rebates for:
    • Bay area commercial biotech and biopharma users
    • University of California San Francisco
  • San Diego Gas and Electric rebate for:
    • University of California San Diego
  • Seattle City Light rebates for:
    • University of Washington
    • Fred Hutchinson Cancer Research Center
  • Stanford University
  • University of California Riverside
  • University of Pennsylvania

It’s quite possible that your research organization could also benefit from a utility or internal energy rebate program for ULT freezer replacement with Stirling Ultracold models.  Contact your utility or Stirling Ultracold representative to help with setting up the rebate process.

The Real Life Cycle Cost of an Ultra-Low Freezer

Did you know that initial purchase price is a relatively small part of the actual cost to own an ultra-low temperature freezer? That’s because the real cost of a ULT is the sum of the purchase price, plus costs for energy, HVAC, floor space and the usual compressor replacement.  With the typical cascade-compressor freezer consuming the equivalent electric power of an average U.S. household, all that energy is rejected as heat in your building, which adds a substantial cost for your HVAC system.

What is your compressor-based ultra-low freezer really costing your organization?
Using manufacturers’ published energy use data at 16c/kWh electric costs, with typical floor space and compressor replacement cost estimates from independent sources, the table on the right estimates cost of ownership percentages per cubic foot of storage per year for a typical compressor-based ULT.

Reduce Total Cost of Ownership by Thinking Strategically

Considering that initial purchase price accounts for less than a third of ULT storage cost, you can see how energy consumption and operating costs have a surprising impact on lowering overall life cycle cost.  Of course, this is counter to the traditional way of thinking about buying freezers.  More research organizations are now looking at that their ULT purchases strategically and replacing traditional models with Stirling Ultracold units.  Using less than half the energy, the SU780UE can typically lower total cost of ownership by about 40%—even with a higher initial purchase price.

In fact, even a free cascade-compressor ULT freezer typically costs more to own than the SU780UE! Watch this video to see how that’s possible . . .

Cooling Performance Integrity Should Not Come with an “Off” Switch

I have good news and bad news.  First, the good news . . .on-off-Switch

With a history of driving up lab utility bills more than their share, it’s good to see compressor-based ultra-low freezer manufacturers aspiring to develop more energy-efficient ULTs.  We applaud this effort and are encouraged to see the lab sustainability imperative gaining a foothold within the research community. In a relatively short time, I believe that Stirling Ultracold has played a positive role in helping to change the industry mindset. By introducing an innovative, energy-efficient cooling technology to the ULT marketplace, we have proven that dramatic sustainability improvements are possible without compromising cooling performance or system reliability.

And now for the bad news . . .

They Want You to Forget that Compromise is Unnecessary

The industry’s move toward energy efficiency has led some to perpetuate the disproven myth that cooling integrity must be compromised to save energy.  In a world that assumes all ultra-low freezers are powered by inherently inefficient compressor technology, this myth actually appears to be true.  However, it’s not true in today’s world, where the Stirling engine is a proven alternative to compressors. That’s why cascade freezer manufacturers would like you to forget that the myth of “necessary compromise” has been disproven by the Stirling SU780UE, through years of third-party data, an independent DOE study and EPA industry-standard test results.

More Bad News: ULT Freezers with Compromise “Built In”

The false axiom that cooling performance must be traded for energy savings and economy has been designed into some compressor-based ULTs.  By offering two operation modes, these freezers either prioritize energy efficiency or cooling performance (i.e. temperature stability) based on operating conditions and/or user selection. However, they can’t have both at the same time!

Is it realistic to ask a researcher, who has years of work depending on the preservation of precious biological samples, to make a choice that reduces cooling performance integrity . . . for any reason . . .at any time?  Energy managers, who have little control over day-to-day ULT storage operation, might well assume that energy efficiency will be turned “off” if there is even the slightest perceived risk to sample security or piece of mind.

Why make this false choice when you don’t have to?  With the Stirling SU780UE, you’ll use less energy than any comparable ULT freezer, while preserving biological samples with the industry’s best cooling performance integrity . . . all at the same time.

What’s the Difference Between “Typical”, “Specification” and “Final Test Method”?

Typical vs Spec vs EPA Final Test MethodFor anyone out there who is confused about which upright ultra-low freezer has the lowest energy consumption in real world conditions, let me make it simple for you . . .

According to test data, publically submitted using the EPA ENERGY STAR® Final Test Method, the Stirling Ultracold SU780UE freezer uses 9.24 kWh/day. No other comparable ULT freezer on the market can substantiate energy consumption this low, using the industry standard test method. By the way, we would be more than happy to send you our test data in the required EPA format.

Reporting a single overall number, this test method was created by the industry and the EPA to provide a simple way for customers to compare ULT freezer’s energy use. This is analogous to the combined city/highway MPG reported for passenger vehicles by the EPA. For example, a 2015 Subaru Outback has a combined city/highway mileage of 28 mpg ( It is well understood by drivers that their actual mileage depends upon a number of factors, including how they drive. Also note that mileage will differ somewhat between one vehicle and another because of manufacturing variability.

While this should be simple, there are different ways to test a freezer and there is confusion out there about what is meant by “typical” versus “specifications” published in sales literature. So let’s look at some definitions . . .

What is the Definition of “Typical”?

The dictionary definition of the word “typical” is, “representative characteristic of a person or thing.” Some within our industry have chosen to represent ULT freezer energy use as “typical” in their published literature. If a number of identical model freezers are tested, this suggests that some units will be more energy efficient while others will be less energy efficient than stated. Given the lack of a clear definition here, it would be reasonable to assume that “typical” is the average, suggesting that about half the freezers will perform worse than typical. This terminology is even less clear, and even less useful, if the manufacturer uses a proprietary test method, which may bear no resemblance to actual operating conditions.

What is the Definition of “Specification”?

The dictionary definition of the word “specification” is, “an act of describing or identifying something precisely or of stating a precise requirement . . . a standard of workmanship, materials, etc. required to be met in a piece of work.” In other words, a specification indicates specific performance that must always be met under the test condition. Our published specification for energy use is “< 9 kWh/day at -80°C setpoint” for the SU780UE in steady state operation with the door closed. (While not as comprehensive as the EPA Standard Test Method, our end-of-line testing procedure balances the industry’s highest energy efficiency standards with the practical time constraints of the production environment.)

To summarize and contrast these two definitions . . . A “specification” is a promise. “Typical” performance is not.

Ask for Test Results Data using the EPA ENERGY STAR Final Test Method

We’re proud of our energy use specification and we test every freezer we manufacture to this standard. Because test methods vary, you should not rely on sales literature when making a ULT buying decision, and you should always ask the freezer manufacturer to provide test data using the published EPA ENERGY STAR® Final Test Method. If they cannot provide this data, you should question the integrity of their marketing material.

The fact that our published spec varies only slightly from the EPA test, which prescribes door openings in the procedure, only proves my point. Integrity and transparency are important in an industry where numbers are thrown around so casually.

By the way the typical energy consumption of our freezers shipped during September was 7.9 kWh/day! This compares to a specification of 9 kWh/day. In the interest of transparency, I am defining “typical” here to mean the average at a -80°C set point in steady state operation―with the door closed.

Stirling Ultracold in Booth #1 at 2015 I2SL Annual Conference

As i2sl conferenceyou may know, the International Institute of Sustainable Laboratories® (I2SL) will be holding its annual conference in San Diego on September 21-23.  Of course, we strongly support lab sustainability initiatives here at Stirling Ultracold, which is why we have participated for the past three years, and will be an event sponsor this year.

I hope you’ll come by and see us in Booth #1 on the exhibit floor at the Hyatt Regency Mission Bay.  We’ll be showing our SU780UE upright ultra-low temperature freezer operating on 110v power at -80° C, using less than half the energy of compressor-based systems.  Please stop by and let us give you a “cool” live demo, including a third-party monitoring system running in real-time on our unit.

During the 8 a.m. Early Bird Session on day 3 of the conference (Wednesday, 9/23), Stirling Ultracold will be presenting a technology demonstration highlighting the impact of ultra-low cooling technology on lab sustainability.  Following that same theme, I would also recommend attending the morning Roundtable on Tuesday, 9/22, entitled Ultra Low Freezers—A Significant Near-Term Opportunity, which will be hosted by Allison Paradise of My Green Lab and Anna Levitt from University of California, San Diego.

As we’re making our final booth preparations and travel arrangements to head west, I just wanted to make sure you’re aware of this important event and invite you to connect with us while you’re there.   As of the date of this posting, it’s not too late to register for the 2015 I2SL Annual Conference, if you haven’t already.

Innovating and Manufacturing Ultra-Low Freezers in Athens, OH USA

Stirling Ultracold graphic highlighting Athens, Ohio locationBack when we were just a small group of inventors with the audacious goal of revolutionizing the ultra-cold temperature storage industry, we could have established Stirling Ultracold just about anywhere. So . . . of all places we could have built our future, why did we choose a small Ohio town in Appalachia? Why did we believe that Athens, Ohio was the right place to innovate and manufacture the best performing, most sustainable ultra-low freezer in the industry?

Why Athens?

Stirling Ultracold employee working on ULT assemblyWe made a conscious commitment to developing a U.S.-based workforce and a growing entrepreneurial culture in a region that had already established a legacy of ultra-low freezer manufacturing. Since opening our facility in 2011, I’ve been gratified and humbled by the positive impact our growing manufacturing operation has had on the lives of our people, their families and our small community. Nevertheless, the decision to locate in Athens has given back even more, supporting our growth on several levels…

Stirling Ultracold employee walking by ULTsWe have benefited in many ways from our close proximity to Ohio University, supported by the Voinovich School of Leadership and Public Affairs, Hocking College, and a surprisingly well-educated community that has helped us fill a variety of jobs, in a range of skill-levels. With startup assistance from TechGROWTH Ohio and the Ohio Entrepreneurial Signature Program (ESP), we have successfully transformed from a small R&D shop to a growing manufacturing organization. Starting from a base in Athens, Ohio, our goal is no less than becoming the #1 ultra-low freezer manufacturer in the world.

It’s from here that Stirling Ultracold products make it possible to find cures for diseases and sustain our environment, all at the same time.

Stirling Ultracold Can Help Increase California Research Funding by Nearly $60M/Year

Market Assessment of Energy Efficiency Opportunities in Laboratories
Market Assessment of Energy Efficiency Opportunities in Laboratories

If you’ve been reading this blog, you know that we like to share reports about the impact of sustainability and energy efficiency on the research community.  The Market Assessment of Energy Efficiency Opportunities in Laboratories is one such study by the Emerging Technologies Coordinating Council.  Prepared by Allison Paradise of My Green Lab, as part of the Center for Energy Efficient Laboratories (CEEL), this revealing report resulted from a collaborative sponsorship of Pacific Gas and Electric Company, Southern California Edison and San Diego Gas and Electric.

The purpose of this study was to:

  1. Estimate the number and types of labs in California;
  2. Estimate the number and types of energy-consuming and water consuming equipment used in California labs;
  3. Assess operational and behavioral opportunities for efficiencies in how laboratory equipment in California is used; and
  4. Estimate the amount of energy used by lab-related facilities and systems.

Representing the largest, most comprehensive investigation of its kind in the California laboratory research market, the results of this study support the creation of energy efficiency programs specifically targeting laboratory equipment. Not only does this study clearly show that there are tremendous potential energy savings for laboratories, but it also points to several independent efforts by the EPA and individual organizations to identify, and whenever possible incentivize, energy efficient equipment and operations.

Ultra-Low Freezer Findings:
Among the many survey results, there were a number of key data points relating to the use of ultra-low freezers that I found interesting for obvious reasons.  One noteworthy finding suggests that there is up to 648 million KWh of electricity being used per year to power -80° C freezers in the state of California, alone!

Now consider this . . . Last year, it was reported by the U.S. DOE-sponsored, Better Buildings Alliance independent study that the Stirling Ultracold SU780UE ULT freezer used 66% less energy than the average cascade-compressor model ULT.  Considering that today’s commercial electric rates are $0.138/KWh in the state of California (per the U.S. Energy Information website), it can be calculated from this recent study that California labs could potentially save up to $59,019,840 per year in energy cost, by simply replacing cascade ULT freezers with Stirling models.  Below is a breakdown of the math:

648,000,000 kWh CA Freezer Annual Energy Use (max.)
$0.138/KWh Avg. CA Commercial Electric Rate
66% Energy Reduction (SU780UE vs. avg. cascade ULT freezer)
$59,019,840/Year Potential Energy Cost Savings in California

While that’s a lot of energy and cost savings from just one state, this doesn’t even account for the facility HVAC energy cost savings that labs will achieve, as Stirling freezers also reject less than half the heat of cascade ultra-low freezers (see our blog post, The Hidden Benefit of Energy-Efficient ULT Freezers).  And of course, let’s not forget the potential sustainability impact that transcends monetary benefits.

At Stirling Ultracold, we salute the excellent work that My Green Lab is doing with utilities and we look forward to the long-term impact that this study will have on the research community in California and beyond!

The Hidden Benefit of Energy-Efficient ULT Freezers

It’s no secret that cascade-compressor, ultra-low freezers require large amounts of energy for cooling.  And we know from the first law of thermodynamics that all this energy can’t just be erased, and will be converted into heat.  Outside of the cold box, ULTs are essentially heaters!  Accordingly, an energy-efficient freezer produces less heat because it uses less energy.  That’s why a Stirling Ultracold freezer that uses less than half the energy also rejects less than half the heat.

The Hidden Energy and Cost Benefit – Less Heat Rejection

So, the more ULTs you have running in ULT Heat Rejectionyour research facility, the more heat that must be removed to keep surrounding spaces from becoming uncomfortably hot. What is often overlooked is the HVAC energy cost required to remove that heat.  Based on ASHRAE guidelines, removing the amount of heat typically produced by a single cascade ULT can add an HVAC load of about 6 kWh/day. This is not inconsequential if you consider that the power needed to remove the heat from just two cascade freezers is 25% more than the power used by our 27.5 cu. ft. SU780UE freezer!  Now consider this energy and cost savings multiplied by 100s of ULTs operated in a research facility.  It really adds up.

And don’t forget that hot ambient air around a freezer adversely affects temperature recovery time when the door is opened and that system heat contributes to the disappointing failure rates of compressors.

Impact on New and Upgraded Facilities

For architects and engineers designing new labs or replacing research facility systems, energy-efficient freezers can have a real impact.  By accounting for markedly lower energy consumption and heat rejection, laboratory designers can specify lower-capacity, less-expensive power distribution and HVAC systems. This reduces both the initial cost of the project and the long-term operating cost of the facility.

Third-Party Data Shows Stirling Uses Less than Half the Energy in Real Time

You can now view Stirling Ultracold’s ULT Freezers’ energy-efficiency in real time on the CSIRO Freezer Energy Monitoring Dashboard provided by the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia’s national science agency.  With the excellent help of our distribution partner, Bioline, this live feed continually monitors the power output of three ultra-low freezers. This live comparison shows our freezer using significantly less than half the energy of the competitors’ cascade freezers.  Now you don’t need to take our word for it, just go look at the data in real time!

Energy Monitoring Real Time
Full day hourly energy usage average of ULT Freezers. (source:

You’ll note that the Stirling SU780 uses far less power than the other two freezers, even though it’s cooling a larger volume.  In fact, if you compare our 780L freezer (27.5 cu. ft.) with the cascade freezer listed at 386L (13.6 cu. ft.), you can calculate that the Stirling uses about a quarter of the energy per liter.

With a respected governmental research agency now monitoring and sharing this energy comparison data in real time for the world to see, there’s really no reason left to doubt the generous energy and cost savings delivered by Stirling freezers over cascade-compressor models.