In case you missed it, here is the link to Buff Grace’s presentation to our adult forum: https://stjohns-mpls.org/sermon/september-28-community-forum/
We want to answer your questions! There were no specific questions this week, but here is some more information on some of the points brought up in Buff’s presentation.
One of the financial opportunities that we can leverage with a solar system is based on the savings on our electric bill, or what we won’t have to pay to Xcel anymore. These are expected to be around $9000 a year for the first few years and could be more as Xcel increases their rates. Could we budget these dollars for something else?
How do you figure out carbon offset?
When a carbon-based fuel is burned, a byproduct of combustion is carbon dioxide, a greenhouse gas. The molecular weight of carbon is 12 g/mol. The molecular weight of oxygen is 16 g/mol. When one carbon atom combines with 2 oxygen atoms, this equates to 12 +16+16 or 44g/mol. Thus, CO2 weighs 3.67 times more than carbon. The source of the carbon is any fossil fuel that is burned. That could be coal, gas or oil. The fuels vary by the amount and type of carbon atoms, but they all still combine with oxygen to create carbon dioxide. When a power plant produces electricity, each kilowatt produced will create a quantity of carbon dioxide or the predominant greenhouse gas.
A carbon offset is compensation for greenhouse gas emissions. If the amount of GHG is known, and the amount of GHG used or emitted by an entity is known, then you can determine the offset. A tree can sequester or absorb about 21 to 70 pounds of CO2 per year depending on species, age and environment. If a tree can absorb 50 pounds of CO2, and the CO2 per year emitted by a facility is 3000 pounds, then it would take about 60 trees to balance it out. These trees would have to grow for a few years to do the job so it would be difficult for us to plant our way out of this problem.
There are a lot of factors that go into these calculations. Fuel source, averages, efficiencies, mixtures, etc. are all factors and they are different for each component. To help you determine this yourself, there are many carbon offset calculators available. The one supplied by the EPA is found at https://www.epa.gov/energy/greenhouse-gas-equivalencies-calculator
Let us know your thoughts!
Sarah, Doug, and Allen
