L6. The Biorenewable Option

We have spent the last five lessons providing an overview of natural resources. We have looked at our rising consumption and have seen the link between consumption and natural resource extraction. We also learned that the extraction of natural resources results in environmental impacts and we have a tool to evaluate these impacts called Life Cycle Assessment.

During the rest of the class we will use this knowledge base to assess biorenewable resources. We will learn about our supply of bioresources and how bioproducts and biofuels can replace some (or all) of our non-renewable resources. More importantly, we will evaluate which products:

are more environmentally friendly
are more sustainable
are truly renewable
benefit national security
are more economical

Read Chapter 8 pages 131-137 of Irresponsible Pursuit of Paradise.

Introduction

Do you live in a house made with wood? Are your kitchen cabinets made out of wood? Have you used any paper today? Kleenex? These are all made of wood - a biorenewable resource. But also, have you driven a car or ridden on a bus today? Have you used cosmetics such as skin cream, shampoo Links to an external site., or mascara? Did you do laundry? Did you take a nutritional supplement? Did you drink water or Coca-Cola out of a plastic bottle made from plant material? Are you wearing anything with cotton or wool? All of these were made from biorenewable resources (or likely contain ingredients from biorenewables) too!

Biorenewable Resources

So what exactly is a biorenewable resource? Let's break down the term starting from back to front:

Resources – If you remember from our first lesson, natural resources are the materials humans use to fulfill wants and needs (i.e. food, shelter, clothing). Resources can be either renewable or non-renewable and include minerals, fossil fuels, solar, air, water, soil, etc.
Renewable – the resources can regenerate within a relatively short period of time, and can be sustainably managed to ensure they are available for future generations.
Bio – the resources are derived from living things like plants, algae, microbes, and animals. Water is a resource and it is renewable, but not “biorenewable”. Solar energy is also renewable, but not “biorenewable”.

This definition is pretty clear, basically plants. But did you know that a big category of biorenewable resources is waste produced from agriculture, forestry, and industry? These wastes include:

Logging residues (woodchips, bark, sawdust)
Crop residues (leaves, stalks, husks, etc.)
Yard and garden waste
Municipal solid waste (garbage)
Waste from food processing plants
Municipal sewage
Animal manure

Biomass is a general term you may also see, in addition to “biomass sources” or "bioresources". All are used to describe biorenewable resources.

In this course we will focus on those non-food bioresources used for producing energy (bioenergy) and bioproducts. However, we must understand that the production of food may compete for the same resources, water or land, as the production of biorenewable resources for bioenergy and bioproducts.

Introduction to Bioenergy

energy_consumption_by_source_large 2017.jpg Most of our energy for heating our buildings, driving our cars and producing electricity comes from non renewable resources. Energy from fossil fuels (petroleum, natural gas, and coal) make up about 80% of US energy. About 9% comes from the mineral uranium, used to produce nuclear energy. The other 11% is from renewable sources. About half of this renewable energy comes from wind, solar, and hydro power while the other half, about 45%, is from biorenewable resources (sometimes referred to as biomass).

If you break down this large "biomass energy" category about half of it comes from wood and wood waste and is used to make electricity and heat. The other half is from biofuels (ethanol from from corn or biodiesel primarily from soybeans). Biofuels are used to replace gasoline and diesel fuel. As we will see in later lessons, there is potential for even more of our energy to come from biorenewable resources.

Biomass (in the form of wood) was the only energy source until coal started being used about 150 years ago. The other source of bioenergy that does not show up on the following graph is oil from whales which was used as fuel for lighting and cooking. Use of whale oil for energy peaked in the 1850s. Similar to wood, the use of whale oil ended with the discovery of cheap petroleum.

Figure 2. History of Energy Use in the USA. (Source: EIA)

We are using about the same amount of biomass for energy now as we did in the early 1900’s but our energy consumption is now about 50 times greater. This additional need for energy has been supplied primarily by fossil fuels. Nuclear energy has been growing since about 1975. Hydro has been around a bit longer but only represents a 2-3% of our total energy. Only in the last 15 years have we started using solar and wind. Even today wind and solar combined represent only about 3% of our total energy use in the US.

Using biomass for energy is important because it is renewable and it is widely considered a more sustainable option than fossil fuels. Is this true? We will be looking more at this question later in the course.

Introduction to Bioproducts

Bioproducts Links to an external site.(sometimes referred to as bio-based products) include both conventional fiber products such as cotton or wool clothing, wood for furniture or construction or paper, and the new or emerging products such as pharmaceuticals, plastics, adhesives, and a variety of industrial chemicals. The USDA estimates that there are over 40,000 bioproducts in existence today.

Table 1. Common Non-energy Products from Biorenewable Resources

Biorenewable Resource	Bioproducts
Corn	Solvents, pharmaceuticals, adhesives, starch, resins, binders, polymers, cleaners, ethanol
Vegetable Oils	Soaps, detergents, pharmaceuticals, inks, paints, resins, cosmetics, fatty acids, lubricants,
Wood	Paper, building materials, fibers & polymers, resins, binders

A Bit of History

Bioproducts are not new! Non-renewable resources, iron, aluminum, plastic, fossil fuels, etc. haven’t always played such an important role in human history. In fact, early human society was based on the exploitation of biorenewable resources – for heat, illumination, and tools. Cotton has been spun for 12,000 years, and sugars have been fermented and turned into ethanol for 6,000 years. As shown in the second graph, biomass (wood) was the primary energy source for societies until the mid-1800s. In his article “The Once and Future Carbohydrate Economy Links to an external site.”, David Morris describes a centuries-long battle for economic dominance between biorenewable resources (referred to as carbohydrates/vegetables) and non-renewable resources (which he calls minerals/hydrocarbons):

Less than 200 years ago, industrializing societies were carbohydrate economies. In 1820, Americans used two tons of vegetables for every one ton of minerals. Plants were the primary raw material in the production of dyes, chemicals, paints, inks, solvents, construction materials, even energy. Cotton and wood pulp provided the world's first plastics and synthetic textiles. In 1860, corn-derived ethanol was a best-selling industrial chemical, and as late as 1870, wood provided 70 percent of the nation's energy.

As the vast forests of the Northern Hemisphere were depleted, coal replaced wood for energy in Europe and North America. The production of bio-based products continued to decrease rapidly in the 20th century (with the exception of lumber, fiber cloth, and ethanol fermentation) as petroleum-based products became cheaper and easier to produce.

Today's Bioproducts

Many of the chemicals used today could be bio-based (made from biorenewable resources) but are currently made from petroleum. This is because petroleum based products are much cheaper than the same products made from bioresources. Table 2 shows how significant this production difference is.

Table 2. Products made from petroleum vs biomass.

Product	Total Annual Production (million tons)	Derived from Plants
Plastics¹ Links to an external site.	320	Less than 1%
Adhesives^{2 Links to an external site.}	9.8	About 1%
*Surfactants³ Links to an external site.	18	About 2%

*A surfactant is a substance that tends to reduce the surface tension of a liquid in which it is dissolved.

Although the proportion of industrial products from biomass is small, biobased products are high value and make a substantial contribution to the US economy as many companies are wanting to be more sustainable. As of 2014, the contribution of biobased products to the Gross Domestic Product (GDP) (the total value of goods produced and services provided during one year) was estimated at 2.3%. (This does not include bioenergy products.) In comparison, the oil and gas industry comprised 7.6% of the GDP in 2015. (GDP Explained, Links to an external site. and Bureau of Economic Analysis Links to an external site.).

Table 3. Contribution of biorenewable resources to U.S. economy.

Product	Contribution to GDP (billions of dollars)	Percent of total GDP (year of data record)
Biobased products (USDA) Links to an external site.	393	2.3% (2014)
Ethanol (US DOE) Links to an external site.	44	0.2% (2015)
Biodiesel (US DOE) Links to an external site.	8.4	0.05% (2015)
Oil and Gas GDP Explained Links to an external site.	1277	7.6% (2015)
Residential Construction (GDP Explained) Links to an external site.	504	3% (2015)

Some questions to consider when moving forward with our discussion of biorenewable resources include:

What products made from biorenewable resources can't be made from non-renewable resources?
What products from non-renewable resources can be replaced with biorenewable resources?
What are the environmental benefits of products made with biorenewable resources?

And to leave you with something possibly a bit more interesting and practical, check out this next 1 minute video for a new bioproduct being developed by students at University of Colorado-Boulder.

Remember to read Chapter 8 pages 131-137 of Irresponsible Pursuit of Paradise.