PT150 S2 Q7 ExplanationGeothermal power plants produce power

Answer choices, explained

1. A

   Weak Impact No Change2% picked this

   Conventional power plants, unlike geothermal power plants, release large amounts of pollutants

   This piles on another reason why we would want there to be more geothermal power, but even if geothermal was equivalent when it came to pollution, we'd already be sufficiently motivated to want more of it, since geothermal is cheaper to produce. So while this increases the incentives for getting more and more geothermal plants up and running, it doesn't seem to address the constraint — which is that there seem to only be limited areas of the world where these underground hot pools can be reached by a drill. A potential red-flag here is that this answer is already true. We're looking for something that will be changing so that "in the near future" we'll go from having geothermal in "limited areas of the world" to having it "available in most areas".

   2%
2. B

   Weak Impact No Change9% picked this

   A typical geothermal power plant produces at least as much energy as a typical

   It wouldn't really matter to us even if a typical geothermal plant produced less energy. We'd still want to build more of them, since the energy is cheaper. Think about wind farms. I'm sure a typical wind power plant produces less energy than a typical coal-burning plant does, but since the wind power is cheaper and cleaner, we're still willing to build them (we might need 2000 wind farms to make the same energy as 1500 coal-burning power plants, but so what? If it's cheaper, we'll do it.) This does say something positive about geothermal (it's makes at least as much power as a conventional plant), but just like (A), we don't really need to pile on more positives. The fact that it's cheaper power is reason enough for us to want more geothermal plants. It sounds like we just don't have many areas of the world where our drills can currently reach these underground pools. A potential red-flag here is that this answer is already true. We're looking for something that will be changing so that "in the near future" we'll go from having geothermal in "limited areas of the world" to having it "available in most areas".

   9%
3. C

   Opposite5% picked this

   The high start-up costs of geothermal power plants discourages their construction even in locations where they are more economical than conventional power

   This is a negative about geothermal plants that would potentially keep them from being constructed. We want an answer that shows us something is changing that will allow us to make many more of them in many more areas.

   5%
4. D

   Correct79% picked this

   Advanced drilling technology is being developed that will soon make it both feasible and economical to drill wells many times deeper than

   Why this is right

   This has the lovable quality of dealing with a change, ("soon" = "in the near future"), and dealing with what seems to be the current technical hurdle holding us back. If there are only limited areas of the world where we can currently reach this hot water by drilling, then we won't be able to make these power plants available in most areas unless we somehow solve this technical hurdle. This is saying that soon we'll be able to drill wells many times deeper than we currently can. Okay. Was depth the problem? Is that what's currently limiting us? It's not 100% clear, but that would seem to be the most conservative common sense guess. After all, if you're saying you can't currently reach something by drilling, it could mean several things: - the drill doesn't go deep enough (we can't reach the underground hot water because it's lower than we can drill) - there are things like schools / hospitals / monuments / etc. that are occupying the sites where we'd love to drill a well (so we can't reach the underground hot water because people won't give us permission to drill a well in a given spot) Both of those are plausible, but the first one is definitely the more conventional meaning of "can't reach with a drill". The second one isn't really saying the drill is holding us back, but "can't drill there because we're not allowed". At any rate, this answer ends up being the only one talking about something that will change in the near future that could be a game-changer when it comes to our current problem of only having limited areas of the world where our drills can reach the underground water.

   Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.

   79%
5. E

   Mixed Impact5% picked this

   Recent research has led to discoveries that could significantly lower production costs for nearly all

   This is weak language "it could lead to significantly lower costs", so compared to the correct answer it has less impact. And since it would cut costs for nearly all types of power plants, it would probably make conventional power plants cheaper, so it may be providing a reason why people would continue building conventional plants, as opposed to geothermal plants.

   5%