Hemp MythBusters — Can hemp biodiesel replace standard diesel?

The Myth

Hemp biodiesel can replace standard diesel.

The Background

We all know what diesel fuel is but what exactly makes it so special and different than gasoline?

Diesel fuel is a special kind of fuel. It is a less refined product compared to gasoline and is the primary fuel for large motors including:

  • Class 8 vehicles (buses, semis, garbage trucks, etc.)
  • Ocean bound ships
  • Rail locomotives
  • Construction equipment (bulldozers, excavators, dump trucks, etc.)

In these applications, diesel fuel is able to offer various benefits compared to gasoline including:

  • Higher torque
  • Higher compression ratios
  • Higher energy density

Biodiesel has been an up and coming fuel for many years. The process to produce biodiesel is called transesterification. Many different plant and animal oils can be utilized to make biodiesel but the most common are (according to the EIA):

  • Soybean Oil (52%)
  • Recycled feeds (13%)
  • Corn oil (13%)
  • Canola oil (12%)
  • Animal fats (10%)

So, we are going to jump in, review the data, do a little math and see just how true this hemp myth really is.

The Data

For this myth, we will focus on a few primary points including:

  • The amount of land required for hemp biodiesel to replace standard diesel
  • Cost differentials
  • Effect on the food supply
  • Technical complications

How Much Land?

As always, to replace a fossil fuel energy source with a plant based source, large amounts of land are required.

According to the Ministry of Agriculture and Forestry of the Government of Alberta, Canada, 1,074 pounds of hemp seed can be produced per acre using hemp grain strains. It has been our experience, working with the Katani strain, from HGI, that 21% of the total seed weight can be pressed into hemp seed oil. This results in an oil weight of 226 pounds per acre.

According to the EIA (Energy Information Association, a US Government Agency), 11.9 billion pounds of oil was utilized to create biodiesel in the United States in 2017. For hemp to just replace that, we would need 52,654,867 acres of land or 22.6% of US farmland based on the Farm Service Agency, August 1, 2019 data.

Now, this is just for hemp biodiesel to replace existing biodiesel production. What would it take for hemp biodiesel to replace standard diesel?

The EIA informs us that the US consumed 41.4 billion gallons of “On Highway Distillate Fuel Oil” in 2017. This is just a longer name for diesel fuel. How much does that fuel weigh?

Diesel weighs about 6.9 pounds per gallon. So the total weight of diesel fuel consumed in the US is 285.7 billion pounds of diesel. That is a lot! But we need to translate that to acres required for hemp to replace it.

As calculated above, an acre of hemp can produce 226 pounds of oil. If we do a little math, we find out that a total of 1.26 billion acres of land are needed to produce enough hemp seed oil to equal the weight of standard diesel fuel consumed. The US is only 2.4 billion acres.

In order for hemp biodiesel to replace standard diesel, 50% of ALL land in the US would be needed to fulfill this order.

If we just wanted to replace standard biodiesel instead, we would need to use 22.6% of all US farmland.

So far it seems that we do not have enough acreage to grow enough hemp to make hemp seed oil to replace standard diesel fuel.

What is the cost?

For biodiesel to be cost competitive with standard diesel, it needs to maintain a sales price of $2.933 per gallons using AAA’s current national price average.

Let’s explore the supply side, the willingness of farmers, from an economic standpoint, to produce a crop at the above price point. We will calculate the value per pound of a diesel replacement and see just how much a farmer would make per acre.

Again, that gallon of diesel fuel weighs 6.9 pounds. Given that, the value per pound is $0.425 per pound. All things being equal, lets just say that the farmer will receive the full retail value at the pump. With a per acre yield of 226 pounds of oil multiplied by the value per pound of $0.425, we can see that a farmer, in this scenario, would gross $96.05 per acre. Going back to the HGI pricing and seeding rate, the farm would be underwater by $8.95 per acre just to buy the seed, let alone put it into the ground, grow it and harvest it.

Now the other thing with this scenario is that the farmer would not get retail pump value. The EIA states that the wholesale, low sulfur diesel price is $1.96 per gallon (using the most expensive area, Los Angeles). That is 66.8% of the value of the national average retail price. Given that, if a farmer was to sell wholesale (assuming that their oil is capable of being a fuel without refining, which it is not), they would only gross $64.16 per acre.

The only way a farmer can maximize the value of the oil, as a diesel fuel source, would be to plant it, harvest it, refine it into biodiesel, transport it and sell it at the retail level at a gas station they own. But again, they will still lose at least $8.95 per acre, only considering the cost of seed.

So far we can see that no farmer would want to grow hemp just to harvest the oil to make biodiesel.

For fun, let’s take a look at the demand side, shall we? This will be how much refiners would have to pay to make biodiesel.

According to the Alternative Fuels Data Center biodiesel is made by reacting some type of plant oil (or animal fat) with a short chain alcohol and catalyst. They further state that 100 pounds of plant oil in will yield 100 pounds of biodiesel out. This makes conversion easy. The next question is, how much is hemp seed oil?

The lowest price I could find was from Bulk Apothecary with a price of $3.63 a pound. Remember that a gallon of diesel weighs 6.9 pounds and every pound in equals a pound out. So our price per gallon just to buy the oil is $25.05. This does not include shipping the oil, refining, shipping refined product or retail costs. Let’s look at the graph to see a comparison:

We can see that biodiesel from hemp seed oil would be extremely expensive. Imagine filling up your tank (let’s say it is 10 gallons) and paying $250.50 at the pump. Compared to Soybean Oil (which is used as the feedstock for the majority of biodiesel, according to the EIA), hemp seed oil is nearly 13 times more costly.

For hemp seed oil to be competitive, the price would have to decrease by 92.2%. That is to be a replacement for Soybean oil in biodiesel, for standard diesel, it is more.

With that, it is quite apparent that hemp biodiesel will not be able to replace standard diesel fuel from the supply side or the demand side. Farmers would lose money on every acre grown and consumers would see prices at the pump undergo extreme price increases.

Reducing Food Supply

This section will circle back to the total land requirement as food supply is a function of the available land.

To produce enough hemp seed oil to produce hemp biodiesel to replace standard diesel, we will need a lot of acreage. 1.26 billion acres to be exact, over 50% of ALL US land.

So we can’t grow enough hemp in the US to replace US standard diesel. But let’s just put that aside and say we can. We need to see what effect that could have on food supplies.

Let’s use some more statistics to figure out how many people would be affected:

  • 7.5 billion — population of Earth
  • 4.62 billion — acres farmed on Earth (USGS Survey)

Given those values, it would be safe to say that each acre on Earth supports 1.62 people (there are 62% more people than acres farmed). That 1.26 billion acres we would need to farm (fun fact: that would require 27.3% of all farmable acres on Earth), would result in about 2.04 billion people losing access to food. That is so outrageous lets consider hemp biodiesel replacing standard biodiesel instead.

For this we would need 52,654,867 acres of land which would translate to 85.3 million people losing access to food.

Now hemp seeds can produce protein along with the oil. Oilseedcrops.org informs us that hemp can produce 5 to 45 bushels per acre (44 pounds per bushel). Given that one acre of hemp can produce 220 pounds of meal to 1,980 pounds of meal. That could be applied into the food market.

However, a bushel of corn weighs 56 pounds and a single acre can yield 178 bushels according to Farm Bureau (fb.org). That is equal to 9,968 pounds of corn per acre, shelled and off the cob. To replace standard biodiesel, let’s look at what would happen if the hemp acres replaced the corn acres. With the oil going to fuel and the protein going into the food market to replace the lost corn, we can calculate that only 68.24 million people would go without food (this is due to hemp, at best, can produce only 20% of the grain that corn can).

Now we can see that even if we had the land and the economics were favorable, the lost crop production would likely result in the loss of food supplies that would affect tens of millions of people. That is just the replace standard biodiesel, let alone standard diesel. If we really look at the myth and the amount of land required, billions would go without the food they need.

The technical issues

Now for any biodiesel to replace standard diesel, regardless of hemp use or not, there will be a number of technical issues including:

  • Reduced energy content (117,000 BTUs for biodiesel to 131,000 BTU petroleum diesel). This leads to lower power and lower overall fuel economy and range. (PennState Extension)
  • High cloud point (30–50 degree cloud point). Leads to clogged fuel lines, clogged filters and problems with cold starting. Further, different feedstocks maintain different cloud points which can lead to quality consistency problems. (Bell Performance)
  • Water absorption. Biodiesel is able to absorb and hold water. This water can reduce autoignition as water is non combustible as well as leading to ice formation within the fuel system in colder climates. Further, biodiesel can be a food source for bacteria and other microbes which can grow within the absorbed water and lead to clogged fuel filters and more rapid degradation of the biodiesel. (Bell Performance)

These issues have been documented for biodiesel from existing sources. But the production process is the same, regardless of source. With that we can expect similar performance issues may occur with hemp biodiesel.

The Myth — BUSTED

With all of this data, the myth “hemp biodiesel can replace standard diesel” is BUSTED.

There are significant problems with this myth. First and foremost in our opinion, is the cost differential for hemp biodiesel relative to existing biodiesel blends, let alone petroleum diesel. Further, the amount of land required is extreme and if that land was used to cultivate an energy crop, large populations could face food shortages. To overcome this, the amount of oil produced per acre would need to increase significantly and the opportunity cost of hemp seed oil in the food industry would have to become saturated in order for price compression to ensue.

Lastly, the technical issue around biodiesel makes the fuel much less attractive through the “drop-in” lens. It is possible that it can be utilized with little engine modification but the fuel consistency would have to be closely monitored, chemicals added to overcome the issues are have the fuel blended with significant levels of standard diesel fuel.

At this point in time, it does not appear beneficial in any capacity to use hemp seed oil as a fuel source to replace standard diesel fuel. If we are to continue with biodiesel, it seems best to continue utilizing soybean oil and other sources and let the hemp seed oil make its way into the food market.

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