Engineer: Thermophotovoltaic generators are devices that convert heat into electricity. The process of manufacturing steel produces huge amounts of heat that currently go to waste. So if steel-manufacturing plants could feed the heat they produce into thermophotovoltaic generators, they would greatly reduce their electric bills, thereby saving money.

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.

A
There is no other means of utilizing the heat produced by the steel-manufacturing process that would be more cost effective than installing thermophotovoltaic generators.
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, it would be possible for steel-manufacturing plants to feed the heat they produce into thermophotovoltaic generators in such a way that those generators could convert at least some of that heat into electricity.
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 plants would save on their electric bills by feeding heat into thermophotovoltaic generators would be sufficient to cover the cost of purchasing and installing those generators.
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 steel-manufacturing plants rely on electricity as their primary source of energy in the steel-manufacturing process.
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 least some steel-manufacturing plants that could greatly reduce their electricity bills only if they used some method of converting wasted heat or other energy from the steel-manufacturing process into electricity.

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Wildlife management experts should not interfere with the natural habitats of creatures in the wild, because manipulating the environment to make it easier for an endangered species to survive in a habitat invariably makes it harder for nonendangered species to survive in that habitat.

Summarize Argument
The author argues that experts should not change natural habitats to help endangered species because doing so always comes at the expense of nonendangered ones.

Identify and Describe Flaw
The argument fails to consider the possibility that helping endangered species is higher-priority than helping nonendangered ones. By definition, endangered species are at greater risk of extinction and likely need more support. Refusing to change a habitat to protect them, especially when nonendangered species can probably thrive elsewhere, overlooks the urgency of preventing extinction.

A
fails to consider that wildlife management experts probably know best how to facilitate the survival of an endangered species in a habitat
This is irrelevant because the argument doesn’t question experts’ ability to help endangered species. It’s only concerned with the negative effect it would have on other species.
B
fails to recognize that a nonendangered species can easily become an endangered species
This possibility does not pose a problem for the argument. The author recognizes that nonendangered species can be harmed since the author advocates for prioritizing their protection.
C
overlooks the possibility that saving an endangered species in a habitat is incompatible with preserving the overall diversity of species in that habitat
This is irrelevant since the author doesn’t advocate for saving an endangered species, but rather, argues that endangered species should not be saved if it means interfering with their habitat.
D
presumes, without providing justification, that the survival of each endangered species is equally important to the health of the environment
The author doesn’t equate anything to the health of the environment. He only presumes that endangered species are not higher-priority than nonendangered ones.
E
takes for granted that preserving a currently endangered species in a habitat does not have higher priority than preserving species in that habitat that are not endangered
This describes how the author fails to consider that saving a species in danger of extinction may be more important than helping species that aren’t at risk.

13 comments

Company spokesperson: In lieu of redesigning our plants, our company recently launched an environmental protection campaign to buy and dispose of old cars, which are generally highly pollutive. Our plants account for just 4 percent of the local air pollution, while automobiles that predate 1980 account for 30 percent. Clearly, we will reduce air pollution more by buying old cars than we would by redesigning our plants.

Summarize Argument

The company spokesperson concludes that the company will reduce air pollution more by buying old cars than it would by redesigning its plants. She supports this by saying that, while the company’s plants account for 4% of local air pollution, automobiles from before 1980 account for 30%.

Notable Assumptions

The company spokesperson assumes a net benefit of disposing of old cars without considering any costs, like how car disposal methods might impact pollution. She also doesn’t consider other factors that might reduce the benefits of the plan, like how many old cars and what kinds of old cars must be disposed of to make a real impact. She also doesn’t address any long-term benefits of redesigning the plants, other than addressing 4% of local air pollution, that might outweigh the benefits of disposing of old cars.

A
Only 1 percent of the automobiles driven in the local area predate 1980.

We know that cars that predate 1980 account for 30% of local air pollution. Even if only 1% of local cars predate 1980, that 1% still accounts for 30% of local air pollution. Thus, (A) doesn’t point out an unaddressed factor that would reduce the benefit of car disposal.

B
It would cost the company over $3 million to reduce its plants’ toxic emissions, while its car-buying campaign will save the company money by providing it with reusable scrap metal.

The spokesperson’s conclusion is about how the company will most effectively reduce local air pollution. Whether the company also saves money in the process is irrelevant.

C
Because the company pays only scrap metal prices for used cars, almost none of the cars sold to the company still run.

This highlights an unaddressed factor that greatly reduces the benefit of the car disposal plan. Cars that aren't running don’t contribute to air pollution. So, if most of the cars the company buys aren't running, the company is not effectively reducing local air pollution.

D
Automobiles made after 1980 account for over 30 percent of local air pollution.

The spokesperson’s argument only addresses the pollution caused by cars made before 1980. The pollution caused by cars made after 1980 is irrelevant.

E
Since the company launched its car-buying campaign, the number of citizen groups filing complaints about pollution from the company’s plants has decreased.

Citizen complaints about pollution don’t necessarily reflect the actual amount of pollution. The spokesperson's argument is about which method will best reduce pollution, not which will best reduce citizen complaints.


34 comments