Making use of Delta T: Reducing industrial energy emissions with mechanical insulation

Blog in Brief

Properly designed and installed mechanical insulation is a great way to reduce energy expenditure, limit a facility’s greenhouse gas emissions and save money. The high Delta T – the temperature difference between two elements, in this case the pipe operating temperature and ambient conditions – of industrial pipes means that curbing the temperature bleed from a pipe’s outer surface into the atmosphere lowers the strain on the overall system, improves process control and limits energy expenditure. When looking to improve the carbon footprint of a facility or to limit the greenhouse gas emissions tied to a building, a simple way is to have an insulation system appraisal done of the site and to make the suggested repairs or additions to the insulation used. The cheapest energy is energy that is never spent, and the simplest way to remove emissions is to not generate them through increased energy use.

Making use of Delta T: Reducing industrial energy emissions with mechanical insulation

Adding insulation is an easy way to improve the energy use in a building, as applying mechanical insulation is an established tool to reduce energy consumption. One rule of thumb is that insulating a bare surface can lower heat loss or impede heat gain by 90-95%.¹ With the increasing focus on improving the energy efficiency of buildings and on designing projects that reach specific certification goals – like LEED – more attention may be focused on the use of insulation in commercial and residential projects.

However, the growing interest in understanding and reducing the carbon footprint of industry facilities also should prompt a look at insulation use in industry. Reducing the energy expenditure needed to provide climate control in facilities and infrastructure lowers the amount of electricity used, limiting the draw on electrical generation and diminishing the emissions from the electrical plant. Cooling a facility is a direct draw on energy use, however, electricity use in heating may be less obvious. Even when heating oil or natural gas systems are in place, electricity can be employed to light or heat the oil or gas and move it through the facility The process helps lower the carbon footprint of industrial facilities not by removing expressed greenhouse gases, but by preventing some from being released in the first place.

In 2020 about 61% of the energy generated in the U.S. relied on the use of fossil fuels. Needing a smaller amount of energy to maintain temperatures reduces the call for energy input and generation.² There also is potential for financial savings from insulating pipes that are well above or below ambient temperatures and have a large Delta T – the difference in temperature between two elements like the surface of a pipe and ambient conditions.

Emission reduction commitments

Interest in reducing greenhouse gas emissions to limit global warming to 2.7°F (1.5°C) has been an internationally targeted goal. As part of the effort, several countries have announced specific individual goals. The U.S., for example, is focused on reducing economy-wide emissions based on its Nationally Determined Contribution (NDC) by 50-52% below baseline levels set in 2005. Canada is seeking to have a 40-45% reduction from 2005 emissions levels. Both countries are working toward a 2030 deadline.

On a similar path, in 2019, New York City set a goal of reducing emissions by 40% by 2030. Part of the process means that buildings with more than 25,000 square feet will need to meet carbon emission limits based on facility occupancy. Buildings must start reporting carbon emissions in 2025. It is unclear if other cities will create similar laws.

According to the U.S. Environmental Protection Agency (EPA), about 45% pf greenhouse gas emissions stem from buildings – industrial, commercial and residential.

Industry also has started paying more attention to greenhouse gas emissions. About 20% of the largest companies globally have committed to reducing emissions, pledging to reach net zero emissions.

Additionally, reporting mechanisms like the Sustainability Accounting Standards Board’s (SASB) Standards are increasing and the SEC said earlier this year that it is interested in reviewing the information provided to underpin the sustainability claims companies make. Reporting on the steps companies are taking is increasing public awareness both of the risk that companies face related to climate change and what companies are doing to address the situation.

Insulation and industry

While there are several ways to offset a carbon footprint and decrease emissions of carbon dioxide (CO2) and other greenhouse gases, application of a sufficient amount of mechanical insulation is one of the most effective.

For example, a full-size pickup truck emits about 406g of carbon per mile according to the EPA. After about 20,000 miles, that adds up to 18,000 pounds of CO2. To offset that much carbon dioxide, it would take planting 360 trees or replacing 310 43-watt incandescent lightbulbs with LED light bulbs.^3,4,5 Alternatively, we could insulate about 8 feet of bare 4-inch pipe operating at 350°F (176.66°C) with 2 inches of insulation.¹ Thinking of the application in industry, as the temperature of the bare pipe increases, the length of insulation that needs to be applied could shrink.

Insulating cold pipes also can help provide an offset to energy use. For example, a 4-inch chilled water line running constantly at 38°F (3.33°C) would have a heat gain of 100 Btu/h/ft with an annual carbon dioxide emission of 89lb/ft/year. Insulating the same pipe with 1 inch of cellular glass insulation would reduce the heat gain to 17Btu/h/ft and the emissions to 15lb/ft/year. Assuming that electricity costs $0.10kWh, the cost per foot of piping would drop from $6.10 per foot per year to $1.05 per foot per year.⁶

Another point to consider when evaluating the utility of insulation to reduce facility costs and emissions is that 10-30% of industrial insulation in current facilities has been found to be damaged or missing.⁶

A tool that can be useful in determining the emissions offset by using specific types of insulation in relevant situations is to consider the material’s Environmental Product Declaration (EPD). The documents are verified by a third-party agency and provide a life cycle assessment of the embodied carbon values in a given insulation or product.

Case study: AstraZeneca

One example of how improving existing insulation or adding new insulation can influence a company’s emissions release can be seen in the program implemented by AstraZeneca. The company set an emissions goal – Ambition Zero Carbon – with the intention of achieving net zero emissions by 2025 and being carbon negative across their value chain by 2030. The program is anticipated to cost about $1 billion and includes multiple elements.

One part of the program was to conduct an insulation system appraisal. The assessment quantifies the amount of energy and money being lost with the current insulation system. It also explores the benefits that could be provided by a more efficient system. The comparison includes how much energy would be saved, the potential improvement in process control and efficiency, the reduction to fuel costs and reduction in emissions.

Public, third-party software must be used during the appraisal to provide transparency and allow for standardization. However, the process has not been standardized by any organization and may not include the scope of work needed in the improvements. The five steps in an appraisal include an interview with the facility manager, a data-collection walk-through of the site, recording data inputs in the software, preparing the final report, and a presentation of findings and information on potential improvements.

The appraisal highlighted several areas where savings could be made at the AstraZeneca facility. The current annual operational costs are about $10,200 but upgrading the insulation could reduce that to $8,000. Improving the insulation could reduce heat flow by 28,060,191 kBTU annually, along with reducing CO2 emissions by 4.49m pounds and nitrous oxide (NOx) emissions 8,994 pounds (see Figure 3 above). The reductions amount to the actions of 4,244 acres of forest for a year, 22 acres of U.S. forest preserved from becoming cropland, or planting 53,732 seedlings and letting them grow for 10 years.⁷

There also can be other benefits to improving insulation. It is easier to control process systems that are well insulated, and improved efficiency lowers the strain on system components, like the boiler, reducing maintenance needs and improving the lifespan. Insulation can curb industrial noise and, when used on hot pipes, lower ambient working temperatures. It also provides a safety measure by reducing surface temperatures on hot pipes that could be touched accidently to 140°F (60°C), lowering the potential for burns. And insulation use can help facilities meet federal safety standards — OSHA standard 1910.261(k)(11) specifies that steam and hot water pipes within reach of the floor or working platforms must be insulated or guarded to prevent contact.

Conclusion

The cheapest energy is energy that is never used and, correspondingly, the easiest way to remove greenhouse gas emissions from the atmosphere is to not emit them. Correctly designing and installing mechanical insulation can address both elements while providing a high return on investment. Insulation also helps improve facility safety and can provide protection from increasingly common severe weather events.

To check our math, or to determine greenhouse gas offsets, the EPA’s greenhouse gas equivalencies calculator is available. And here is more information about the work Owens Corning is doing to reduce emissions production.