Lower emissions through emerging technologies and alternative power.


Over the last few years, the construction industry has faced more than its share of financial challenges. And the industry’s widespread use of diesel-powered vehicles and equipment has attracted attention from both health and environmental advocates. Given the level of exhaust emissions from this kind of equipment, significant environmental regulations have been implemented, and more will come. Fortunately, viable alternatives for on- and off-highway construction vehicles will come to market, allowing industry professionals to comply with regulations while still saving significant time and money.

Emission standards began in the 1970s when highway vehicles became highly regulated. As the benefits of standardizing emissions became evident, government agencies like the Environmental Protection Agency (EPA) started evaluating how other types of engines and fuels also affected the environment. Nonroad or off-road vehicles, widely popular in the construction industry, became the subject of debate and the focus of the government’s increasingly stringent regulations.



The Dangers of Emissions

In 1990, amendments to the Clean Air Act directed the EPA to study how off-road equipment contributed to urban air pollution. The findings have been a major catalyst for the restrictions imposed on the construction industry today. The research found that off-road vehicle engines emit as much nitrogen oxides (NOx), hydrocarbons (HC), carbon monoxide (CO) and particulate matter (PM) as highway vehicles. 

In the case of diesel-powered equipment, these engines emit even more toxins and are also one of the largest sources of PM—known to pose public health problems including lung damage and aggravating existing respiratory disease. 

Unfortunately, the health issues related to emissions do not stop there. According to the Clean Air Task Force, America’s 11 million diesel buses, trucks, trains, ships and construction equipment all emit pollutants that lead to 21,000 premature deaths. Additionally, research has shown these emissions increase the number of heart attacks and asthma cases each year and create a cancer risk seven times greater than the combined risk of all 181 other airborne toxins tracked by the EPA. 

Despite the fact that air quality regulations have become increasingly stringent over the last 20 years, the American Lung Association says that 58 percent of Americans—three out of five people—live in areas with unhealthy air pollutant levels. 



How to Address the Issues

The construction industry uses more diesel engines than any other sector. Whether it’s forklifts, tractors, generators or pumps, most equipment at construction sites integrate diesel technology. The EPA has developed a strategy to help achieve low-polluting engines by implementing new equipment and fuel standards. Goals for the construction industry include:


Retrofit existing diesel vehicles.

With the fast-paced advancements in technology, retrofitting existing engines can translate into savings and help the environment. For instance, some companies specializing in heavy-duty construction equipment solutions have developed technology for equipment to use a hybrid drive system. These systems enable users to save more than 50 percent of fuel, which dramatically cuts down on operation costs and makes up for the investment over time. 


Implement emission testing programs for diesel vehicles.

Although tools and resources vary from state to state, emission testing can be highly effective and serve as a precautionary measure. Conducting these tests early and being responsive ensures that your company operates under EPA guidelines and does not unnecessarily contribute to pollution. 


Administer anti-idling programs


According to the EPA’s construction sector report, “If construction firms could reduce idling of off-road diesel equipment by 10 percent, the resulting greenhouse gas emissions savings sector-wide could total approximately 1.8 billion pounds of CO2 (830,000 metric tons) per year.” 

Idling emits 20.7 pounds of CO2 per hour, depending on the engine size. For example, a 1,000-rpm engine will use approximately 0.81 gallons of fuel per hour, which costs approximately $4,550 per year to fuel each piece of equipment. Scale that to a construction project with a fleet of 50 bulldozers, backhoes and cranes.  A 10-percent cutback in idling would save $22,700 a year. 


Promote cleaner fuels.

During the summer of 2006, refiners began producing ultra-low sulfur diesel fuel (ULSD) with sulfur levels below 15 parts per million (ppm) for use in heavy-duty highway diesel engines. This change created a vast improvement in smog levels by dramatically decreasing particulates in the air. 

The building construction industry can play an important role in controlling this pollution since 30 percent of the 2 million diesel engines used in the industry were manufactured prior to the standardized emission regulations. Heavy-duty equipment such as bulldozers, cranes and forklifts account for 32 percent of all NOx and 37 percent of fine particle emissions expelled in the air. 

So far, Connecticut, New York and Massachusetts have city agencies retrofitting equipment on construction projects. Many joint efforts taking place expand retrofit requirements for construction contracts to other government agencies and institutions across the United States. 



Alternative power

Six major types of alternative power systems and fuels can help reduce environmental impacts: 


1. Hybrid-Electric 

Widely known and gaining in popularity among many eco-conscious consumers, hybrid-electric vehicles (HEVs) combine the benefits of diesel-powered engines and electric motors and can be configured to obtain different objectives, such as enhanced fuel economy, improved power or additional auxiliary power for on- and off-highway construction vehicles. The hybrid technology reduces fuel consumption by as much as 65 percent under normal conditions without reducing performance.


2. Hydrogen 

Hydrogen drive systems can be produced domestically from coal and other fossil fuels including nuclear power or renewable resources, such as hydropower. Fuel cell vehicles (FCVs) powered by pure hydrogen emit no harmful air pollutants. Unfortunately, hydrogen gas is costly to produce, and FCVs are currently expensive to purchase and maintain.


3. Propane-Fueled 

Also called liquefied petroleum gas (LPG), propane is a domestically-abundant fossil fuel that generates less harmful air pollutants. LPG is a clean-burning fossil fuel that can be used to power internal combustion engines. LPG-fueled vehicles significantly lower the amount of harmful emissions and CO2. LPG is less expensive than diesel and gasoline, it can be used without degrading vehicle performance, and most LPG used in the United States comes from domestic sources.


4. Biodiesel 

The United States currently derives about 90 percent of biodiesel from soybeans, with less than 9 percent of production from recycled vegetable oils. Only virgin vegetable oils or animal fats can be sold to meet the standards set to control the quality. 

Switching from petroleum to biodiesel reduces greenhouse gas emissions 25 to 60 percent depending on the type used, and it reduces CO2 emissions by 78 percent. It is also a low carbon fuel. However, biodiesel usage can have important caveats that should be considered and researched before converting equipment. It has different solvent properties from petroleum diesel and can degrade certain engine parts in some models manufactured prior to 1992 if not converted properly.


5. Natural Gas 

Natural Gas is a fossil fuel that is less expensive than diesel and gasoline. Over 85 percent of U.S. natural gas is generated domestically and creates 75 percent less smog-producing pollutants and 35 percent less greenhouse gas emissions on average. 


6. Electric

An electric motor or a generator-powered electric drive system, which has power stored onboard in battery packs, consumes no fossil fuels for propulsion or operation. Manufacturing an electric drive system can be costly, but as technology develops, prices will balance out.

In the long run, green business practices will be critical for a sustainable and profitable business.

By The Numbers


According to the Clean Air Task Force, America’s 11 million diesel buses, trucks, trains, ships and construction equipment all emit pollutants that lead to 21,000 premature deaths.