By Mike Reese, Renewable Energy Director
What would you do for your farming operation if...?
Have you ever thought, ‘What will I do for my farming operation if diesel fuel is $5 gallon and natural gas, propane, and nitrogen fertilizer tripled in price within less than 12 months?’ Welcome to May 2022! Whatever the cocktail mix of geopolitical tensions, economic adjustments, demographic changes, and supply chain challenges that brought us to today, the end result appears to be with us for a while – extremely high input costs!
So now with hind sight in full view, what options are out there? Well, not so many in the short term. However, the mid and long term offers some very exciting options. Here are a couple options that will be discussed and demonstrated at the Midwest Farm Energy Conference on June 15th and 16th at the University of Minnesota West Central Research and Outreach Center.
The first option which will be discussed on the first day of the conference is to locally produce and utilize hydrogen and ammonia directly or as precursors for fuels and nitrogen fertilizer.
We have multiple paths of production for both hydrogen and ammonia in the Midwest using wind and solar energy, natural gas with carbon capture and sequestration, nuclear power, and others production routes such as biogas reformation and biomass gasification.
Hydrogen or H2 is an energy carrier and a building block for vitally important chemicals such as nitrogen fertilizer. Hydrogen itself can be combusted in engines and burners, it can be used to produce electricity within fuel cells, and can be combined with other molecules to form fertilizers and both liquid and gaseous fuels. Hydrogen fuel has its challenges especially from a standpoint of the cost of storage and transportation. This is where our research efforts in green ammonia production come into play. Combining hydrogen with nitrogen through what is called the Haber Bosch Process forms anhydrous ammonia or NH3 which is roughly ten times less expensive to store and transport than hydrogen. We currently use “grey” ammonia (produced from natural gas steam methane reforming) extensively across Minnesota for providing nitrogen to our corn and small grain crops. Ammonia is also a precursor to the other forms of synthetic nitrogen fertilizer used in Minnesota. Because ammonia has a high percentage of hydrogen, it can also be used as an energy source similar to hydrogen and hydrocarbons such as natural gas. Ammonia can be combusted in engines and burners (such as grain dryers) and used directly in certain types of fuel cells. Ammonia can also be “cracked” back into pure hydrogen. Much of our team’s research focus has been on the techno-economics of using green ammonia for storing and transporting hydrogen. Therefore, we have a good understanding of the benefits of converting hydrogen into ammonia. Low to moderate cost AND STABLE electrical energy offered by wind and solar prices is key to making this system work. Nuclear and hydroelectric also contribute to the pricing stability of electrical energy.
To provide some context for our research, let’s explore how zero-carbon hydrogen and ammonia may be produced locally and then used to decarbonize and stabilize Midwest industries such as agriculture.
Nitrogen fertilizer is the next largest world-wide contributor of GHG emissions at 2%. The Midwest has the greatest concentration and largest density of corn and small grain production in the United States, if not the world. From our research, roughly 35% of the fossil energy footprint of corn production is related to nitrogen fertilizer. Green hydrogen can be used in the manufacture of ammonia which is a drop-in replacement for what farmers currently use. Green ammonia may also be used to fuel grain dryers which represents another 45% of the fossil energy footprint of corn production. And, finally green ammonia can be used to fuel tractors and trucks. In combination, we could reduce the fossil energy footprint of corn production over 90% - truly transformational! In turn, the fossil energy footprint of meat, dairy, and biofuel production would be significantly decreased.
Decarbonize Biofuel Production
The ethanol industry currently emits pure CO2 from fermentation. To maintain competitiveness within the market, this CO2 will need to be sequestered in the next 2 to 5 years either through piping the CO2 to deep wells in North Dakota or Illinois or through utilization in chemical production. Green hydrogen could be a key to capturing and utilizing this CO2 through urea, aviation fuel, methanol, ethanol, and other forms of fuels and chemicals. This will be a paradigm shift within the Midwest biofuels industry and put the industry on a path towards long term stability and sustainability.
There are other industries that could also benefit:
Decarbonize the Construction Industry
Zero carbon hydrogen can be combusted for thermal energy within the concrete production process. Quick lime is used for concrete production. Within the manufacturing process of quicklime, limestone mined in Minnesota quarries is heated in kilns. Green hydrogen or ammonia can displace the fossil fuels used in this process. Heating limestone also drives off CO2. Similar to biofuel fermentation, this CO2 can be captured and combined with hydrogen or ammonia to produce fertilizers and liquid fuels.
Decarbonize heavy vehicles and transportation
Green hydrogen and ammonia can be used for marine bunker fuel as well as train engines. Ammonia may also fuel the ore ships on Lake Superior or the barges on the Mississippi River. Major ship builders around the world are currently evaluating the use of green ammonia in marine engines with some ammonia-fueled ships now entering service.
Decarbonize the Electric and Natural Gas Industry
In order for electric utilities to reach 80 to 100% renewable power generation, seasonal storage is needed. The cost of storing electricity seasonally in batteries is exceedingly expensive. Excess wind and solar can be used to produce hydrogen and ammonia which can then fuel power generation when load demands. For the gas industry, green hydrogen and ammonia can also be used to displace natural gas for thermal energy applications- critically important for northern climates like Minnesota.
Decarbonize Steel Production and Mining
Steel production represents about 8% of global greenhouse gas emissions world-wide. Fossil fuels used in heavy mining equipment may be replaced with zero-carbon ammonia-fuel. Similarly, fossil fuels used in the production of iron pellets as well as the carbon purification process could be displaced by green hydrogen. Minnesota could potentially process steel within the State and become an exporter of “green” steel. Similar efforts are underway in northern Sweden and in the Iberian Peninsula to produce “green” steel. The auto-maker Volvo is purchasing “green” steel from the Swedish steel mill.
The second option which will be discussed on June 16th – the second day of the conference is to electrify more loads at the farm. This is called “beneficial electrification”. It can mean many things such as energy efficiency improvements, adding solar PV or wind generation, electrical storage, and electric tractors and vehicles. Utilities generally have long term contracts for the purchase and supply of electricity. Therefore, electrical power is not as severely impacted by volatile markets (even though natural gas, propane, and diesel fuel are used for the production of electricity and rising costs do have some impact on electric bill). In addition, the cost of generating solar PV on farms is decreasing every year with technological improvements and scaling of production. With the introductions of the all-electric Ford F150, Chevy Silverado, Polaris Ranger, Monarch tractor, and a myriad of other all-electric vehicles; one can either use inexpensive grid power or produce power on-farm to charge these vehicles. In many cases, the cost per gallon of gas equivalent is about $1 so very inexpensive transportation energy.
Even though these farm energy technologies may seem unreachable, they may soon help contribute to correcting our current problems. Learn more about the Midwest Farm Energy Conference.