Self-study
Engineer: Support Thermophotovoltaic generators are devices that convert heat into electricity. ███ ███████ ██ █████████████ █████ ████████ ████ ███████ ██ ████ ████ █████████ ██ ██ ██████ ██ ██ ███████████████████ ██████ █████ ████ ███ ████ ████ ███████ ████ ██████████████████ ███████████ ████ █████ ███████ ██████ █████ ████████ ██████ ███████ ██████ ██████
Summary
The author concludes that if steel-manufacturing plants could feed the heat they produce into thermo. generators, they would save money by reducing electric bills. Why? Because the process of making steel makes a lot of heat that currently goes to waste. Thermo. generators can convert heat into electricity.
Notable Assumptions
We know that thermo. generators can convert heat into electricity. And we know that there’s a lot of waste head from making steel. If the generators could convert the heat into electricity, electric bills might be reduced. But does that prove there will be overall cost savings? There might be other costs to take into account — costs of installing, running, and maintaining the generators, for example. The author’s assuming that these other costs associated with the thermo. generator would not outweigh the cost savings from reduced electric bills.
16.
Which one of the following ██ ██ ██████████ ██ █████ ███ ██████████ ████████ ████████
a
There is no █████ █████ ██ █████████ ███ ████ ████████ ██ ███ ███████████████████ ███████ ████ █████ ██ ████ ████ █████████ ████ ██████████ ██████████████████ ███████████
The author never suggested that thermo. generators would be the most cost effective means of using the currently wasted heat. Even if there were more cost effective means, the thermo. generators could still be one way to save money.
b
Using current technology, ██ █████ ██ ████████ ███ ███████████████████ ██████ ██ ████ ███ ████ ████ ███████ ████ ██████████████████ ██████████ ██ ████ █ ███ ████ █████ ██████████ █████ ███████ ██ █████ ████ ██ ████ ████ ████ ████████████
The conclusion is based on the hypothetical situation in which the plants could feed heat into thermo. generators. If that’s possible, the author says, then it would save money. But this doesn’t require an assumption that the hypothetical situation is in fact true with current technology. Even if current tech. can’t do it, we can still argue about what would happen IF it were possible.
c
The amount steel-manufacturing ██████ █████ ████ ██ █████ ████████ █████ ██ ███████ ████ ████ ██████████████████ ██████████ █████ ██ ██████████ ██ █████ ███ ████ ██ ██████████ ███ ██████████ █████ ███████████
Necessary, because if it were not true — if the savings on electric bills would NOT be enough to cover the cost of purchasing/installing the generators — then the generators would not result in “saving money.” The savings from electric bills would be offset by the other costs.
d
At least some ███████████████████ ██████ ████ ██ ███████████ ██ █████ ███████ ██████ ██ ██████ ██ ███ ███████████████████ ████████
Not necessary, because as long as steel plants use electricity at all, the author’s argument can still work. There can still be savings on electric bills, even if electricity is not the primary source of energy for any steel plants.
e
There are at █████ ████ ███████████████████ ██████ ████ █████ ███████ ██████ █████ ███████████ █████ ████ ██ ████ ████ ████ ██████ ██ ██████████ ██████ ████ ██ █████ ██████ ████ ███ ███████████████████ ███████ ████ ████████████
Although the author assumes that some plants could reduce their electric bills by converting heat/energy into electricity, this doesn’t imply that some plants need to use such conversion in order to reduce their electric bills. Even if the conversion isn’t required to reduce electric bills, it can still be a method that would lead to a reduction in electric bills.