Building with Bioplastics - Part 4

July 17, 2012 – Vol.17 No.18

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 4.

Renewable energy plays a significant role.

by Bruce Mulliken, Green Energy News

About halfway through this series, let me recap.

Mother Nature does a pretty good job of capturing and storing carbon dioxide. Plants pull CO2 out of the air, combine the gas with elements of water and, with help from energy from the Sun, make a blend of carbon, hydrogen and oxygen which becomes part of the structure of the plant: the leaves, stalk, stems, roots etc.

If that plant happens to be tree, the carbon that was pulled from the air remains sequestered in the wood of the tree as long as it is alive, or in the case of trees used for lumber, the carbon can be sequestered in the frame of a house, a piece of furniture or other wood-built object. In wood used as a building product, carbon can remain sequestered for at least a decade or as much as centuries.

If that plant is something other than a tree, such as a grass, flowers or food, the sequestered life is much shorter, perhaps as little as a few days, and the carbon is released as soon as these plants begin to decay. Decaying plants can release both carbon dioxide and methane, a simple molecule of hydrogen and carbon.

Using non-degradable bioplastics to build super durable goods, which can sequester carbon for decades, is simply improving on the work of Mother Nature. Instead of wood being a primary, natural way to sequester carbon dioxide, the man-made process could use all kinds of plant life including grasses, waste wood, waste food and waste agricultural products, even algae, to make bioplastics which are then used in the manufacture of products and components used to build super durable goods, like buildings and infrastructure.

Mother Nature does her fine work of capturing carbon dioxide and putting it work building plants with the help of clean and renewable energy: mostly sunlight. Man's method of turning natural carbon-based materials, such as cellulose, into bioplastics with which to build things, should also be energized by renewable energy. And this is where this segment continues the series.

Making anything requires energy. If it’s harvesting feedstock and delivering it to processing facilities, to the thermal and electric energy used to make raw materials, to production processes to turn those raw materials into durable goods, energy is needed from somewhere. Most production processes use fossil fuels or electricity from the grid, which can be generated from wide variety of sources including renewables.

If the goal of using bioplastics to make super durable goods that sequester carbon for decades is to sequester as much carbon dioxide as possible, then energy used to make the bioplastics, as well as energy used to turn bioplastics into products, must be as fossil fuel free as possible. Just like endless clean solar energy used by plants to take carbon out of air and use it in building their own structure, the continuation of the process by man should be equally clean.

If carbon-based fossil energy, such as coal or petroleum, were in used in any part of the process to make bioplastics and then products, the bioplastics would have a carbon footprint, albeit small. It’s the carbon footprint we’re trying to reduce or avoid remember? The manufacturers of bioplastics and bioplastic products would have to follow every step of their processes, their product life cycle, to keep carbon inputs to a minimum.

Fortunately, the renewable energies to turn plant material into bioplastics is already available and could be put to work:

--- Equipment used to tend, harvest and transport bio-feedstocks to make bioplastic could be fueled with renewable fuels, particularly biodiesel for trucks and tractors;

--- Manufacturing facilities or refineries needing heat and electricity to make bioplastics could buy renewable energy from the grid. Facilities could operate with solar thermal power or hybrids that make photovoltaic solar electricity and solar thermal energy at the same time;

--- Even the molding process for turning bioplastic pellets into products can be done using solar energy directly. LightManufacturing, for example has a process that uses concentrated sunlight to generate heat to mold plastics into finished products, perfect for turning bioplastics into salable products;

--- Finally, bioplastic products could be delivered from manufacturing facilities to customers in trucks running on renewable fuels, again biodiesel or hybrids or all-electric trucks.

Bioplastics with the smallest carbon footprint could have a higher value justifying the potentially higher cost of renewable energy inputs in production. In projects where bioplastics are used in government mandated programs to reduce greenhouse gases the bioplastics that have the smallest footprint should have a higher value.

In this new industry to use bioplastics to sequester carbon dioxide from the atmosphere to help mitigate global warming, renewable energy will find new business.

Links.

LightManufacturing

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 2.
Residential bioplastic building materials when managed and recycled could sequester carbon dioxide for centuries.

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 3.
Building big things for significant carbon sequestration.

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 4.
Renewable energy plays a significant role.

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 5.
Which plants for feedstock?

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 6.
Man-made systems to capture carbon dioxide for plastics and other chemicals.

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 7.
The need for a regulated industry.

BUILDING WITH BIOPLASTICS:
ATMOSPHERIC CARBON STORAGE IN CONSTRUCTION MATERIALS - PART 8.
New technologies to convert plant material into chemicals for bioplastics and series wrap-up.