In Western economies, more energy is used to operate buildings

Question

In Western economies, more energy is used to operate buildings than to operate transportation. Much of the decline in energy consumption since the oil crisis of 1973 is due to more efficient use of energy in homes and offices. New building technologies, which make lighting, heating, and ventilation systems more efficient, have cut billions of dollars from energy bills in the West. Since energy savings from these efficiencies save several billion dollars per year today, we can conclude that 50 to 100 years from now they will save more than $200 billion per year (calculated in current dollars).

On which one of the following assumptions does the argument rely?

(A) Technology used to make buildings energy efficient will not become prohibitively expensive over the next century.
(B) Another oil crisis will occur in the next 50 to 100 years.
(C) Buildings will gradually become a less important consumer of energy than transportation.
(D) Energy bills in the West will be $200 billion lower in the next 50 to 100 years.
(E) Energy-efficient technologies based on new scientific principles will be introduced in the next 50 to 100 years.

killthegmatavi · Accepted Answer

The conclusion is that 50 to 100 years from now, they will save more than 200 billion dollars per year in energy bills(based on current prices).
Premise: Energy savings from current new building technologies save several billion dollars every year.
Assumption is something that is assumed for the logical validation from premise to conclusion.
Check the assumptions
On which one of the following assumptions does the argument rely?

(A) Technology used to make buildings energy efficient will not become prohibitively expensive over the next century. >> Sound
(B) Another oil crisis will occur in the next 50 to 100 years.>> Out of scope
(C) Buildings will gradually become a less important consumer of energy than transportation.>> Out of scope of conclusion and premise
(D) Energy bills in the West will be $200 billion lower in the next 50 to 100 years.>> Doesnot support the conclusion
(E) Energy-efficient technologies based on new scientific principles will be introduced in the next 50 to 100 years.>> Sound

Logically negate the options A and E
E> Energy efficient technologies will not be introduced in the next 50 to 100 years: Does this weaken or attack the conclusion that 
We will save more than 200 billion dollars per year. NO it does not negate, as without introducing any new energy efficient technologies premise states that several billion dollars are save every year with the existing technology.

A>Technology used to make buildings energy efficient will become prohibitively expensive over the next century. This attacks and weakens the conclusion. If the technology used to make buildings energy sufficient will become expensive than several dollars saved every year would be reduced and the conclusion will not stand.

Hence A IS THE CORRECT ANSWER

Bunuel · Answer

OFFICIAL EXPLANATION

Unlike Supporter assumptions, Defender assumptions are extremely hard to prephrase because there are so many possibilities for the test makers to choose from. The correct answer in this problem is a Defender, but it is unlikely that anyone could have predicted the answer. Compare this to the previous problem, where many students were able to prephrase the correct Supporter answer. Now, focus on the final sentence of the argument, which contains a premise and conclusion: Premise: Energy savings from these efficiencies   save several billion dollars per year today. Conclusion: 50 to 100 years from now they will save more than $200 billion per year (calculated in current dollars). So, according to the author, the new building technologies—which are already saving billions—will continue to do the same in the future and the savings will be even greater, relatively.

Answer choice (A): This is the correct answer , and a classic Defender. If the money-saving and energy-saving technology becomes too expensive to use in the next 100 years, the savings expected will not materialize. Because this idea would clearly weaken the argument, the author assumes that it does not exist, and answer choice (A) denies that the technology will become prohibitively expensive over the next century.

Answer choice (B): Although there has been an energy usage decline since the 1973 oil crisis, the author does not assume that there will be another crisis in the next 50 to 100 years. Look at the conclusion—does there seem to be a reliance on the idea in this answer? No.

Answer choice (C): Although this answer plays with the idea mentioned in the first sentence of the stimulus—that more energy is used to operate buildings than to operate transportation—no assumption is made that buildings will become a less important consumer of energy. True, buildings have saved billions in operating in costs, but the conclusion is about future savings and not about comparing buildings to transportation.

Answer choice (D): The argument is specific about technologies saving more than $200 billion per year; the author does not assume that the total bill in the next 50 to 100 years will be lower by $200 billion.

Answer choice (E): The argument is about current technologies saving money in the future. The author does not make an assumption regarding new technologies being introduced in the future.

chetan2u · Answer

ans A..
only a and e stand out as probable ans..
however A states the correct assumption that the savings will keep increasing without commensurate increase in spending in these technologies..

fireinbelly · Answer

E seems to be too narrow due to the wordings "Energy-efficient technologies based on new scientific principles". The passages only mentions "new building technologies" Hence E seems too specific to be correct.

Hence A is the only viable option.

souvik101990 · Answer

souvik101990 · Answer

Necessary Assumption
My Thought Process: This is basically saying, "we are saving so much money today and we have been saving more and more for many years. Since we have done so well up until this point, in many years from now we will save even MORE!" The big problem with this argument is that it is assuming that everything (at least as it pertains to energy, money, etc.) will stay about the same and we will continue to save money. What if eventually something happens and all of this great technology becomes ridiculously expensive? Since I am looking at a necessary assumption question, I am thinking to myself "ok what is absolutely necessary for this argument to work?" From there I will eliminate everything that can be negated while still keeping the argument intact.

(A) Yes! This is correct because if we say this is not true and that these new technologies WILL become "prohibitively" expensive then what will happen? The argument falls apart! We won't be saving anymore! We will probably be losing it and there is no way we are going to be saving $200 billion if they become "prohibitively" expensive. If I take this negation, assume its truth, and see the argument fall apart, then that answer choice is correct. This is exactly what I did here and (A) is the correct answer.

rezaulnsu · Answer

To beat the assumption question, negation technique is the best weapon.
After using it, we can tell Answer A is the correct answer since if energy saving equipments become more expensive later, people will use them less.
Option B is irrelevant.
Option C does hold if applying negation technique. If building becomes instead more energy driven, still saving even more than $200 B. so, after negation, it even strengthens rather than weaken the conclusion.
Option D is wrong because of some problems inherent. One is 'bill'. Another is saying $200 B lower but we need more than 200$ meaning $201 or more.
Option E is very tricky and attractive. But negation technique can eliminate it as well, since even if existing technology is enough for the validity of the conclusion. In fact, reading this passage might tempt us to think on new discovery of technologies to come in the future . But here, it is in fact suggested that more saving is possible in the future just because of the natural assumption that day by day new technologies become popular to people. If 40% people use energy saving equipments, in the future more and more people will be attracted to it..even jumped to 70 or 80%.

daboo343 · Answer

Clearly A will be the answer
 if we negate A then
 Technology used to make buildings energy efficient will become prohibitively expensive over the next century and so conclusion falls apart

Prasannathawait · Answer

True, A is the required assumption because if the technology prices go high then we might not get the desired profits.

David nguyen · Answer

In Western economies, more energy is used to operate buildings than to operate transportation. Much of the decline in energy consumption since the oil crisis of 1973 is due to more efficient use of energy in homes and offices. New building technologies, which make lighting, heating, and ventilation systems more efficient, have cut billions of dollars from energy bills in the West. Since energy savings from these efficiencies save several billion dollars per year today, we can conclude that 50 to 100 years from now they will save more than $200 billion per year (calculated in current dollars).

NOW: new tech -> cut cost
FUTURE: 50 to 100 years from now -> SAVE > $200B

The logical chain seems very legitimate and has no GAP here. So it must be the Defender Assumption type, which requires eliminating possibility that can break down the argument.
As we can see from the short-version of the argument. The author argued that just because the tech is currently cutting cost, it'll do the same in the future. Is that so? What If resources become scarce, leading to higher in cost of creating those techs? Then we might not be able to save money in the next 50 to 100 years.

The correct answer must eliminate this or similar possibilities.

On which one of the following assumptions does the argument rely?

Ah ha. This matches our thought. Hang on to this.
 
No where in the argument says that there will be another oil crisis in the future. (B) is out.
 
Yeah that maybe true. But does it affect the conclusion? If this is not true, the conclusion still holds true. (C) is out.
 
Okay, lower bill. However, what if the cost of technology is greater than $200B? Then we end up not saving anything. (D) is out.
 
We only care about the tech that have already been created. Future tech is irrelevant.

A is left. (A) is our correct answer.

GMAT0010 · Answer

A vs E: E says that over time, new technologies will develop. That's all. Does this mean that the expense will decrease? No!!

No link was drawn here! A is the better choice

ligamenttears · Answer

Need expert thoughts:

I was leaning more towards C than A.

C--> If buildings consume lesser energy, your savings effectively reduce vs anticipated savings as of today, right? we are assuming building's consumption will remain high or constant.

A-->The role of tech doesn't effect formula for savings. Generally as well, all energy efficient tech is expensive at the moment but the dollar investment that goes into creating and using this tech is not used to calculate energy savings.

$ Energy savings is simply $ version for energy consumed currently minus anticipated drop due to many reasons (could be tech, eventual lesser consumption, etc)

AlexTheTrainer · Answer

quote]

(C): Can be eliminated for multiple reasons, one of which is the fact that the first sentence (referencing transportation) is irrelevant. We know this because the first sentence does not answer WHY the conclusion is true nor does it provide a factual context for the argument.

It can also be eliminated because energy “importance” is different than energy consumption.

It also can be eliminated because its only compared to transportation. In reality, we have no idea about buildings actual energy consumption beyond the fact that they’ve been falling.

Even supposing that the answer choice talked about gradually less energy consumption, negating the answer (greater energy consumption) merely supports the truth of the irrelevant first sentence. Supporting the truth of anything in the stimulus certainly does not kill the argument.
..........................

(A): For the record, I disagree that the cost of using energy efficient technology is not part of energy savings calculations, but suppose you are correct.

Negating (A) means that energy saving technology is prohibitively expensive. Whether we agree with this or not is irrelevant, especially because it’s a negation. We’re not accepting the negation as truth, we’re testing whether the answer is necessary by negating it and see what happens to the argument as a result.

If the energy saving technology is prohibitively expensive, building owners won’t purchase and use it.

Posted from my mobile device

unraveled · Answer

In Western economies, more energy is used to operate buildings than to operate transportation. Much of the decline in energy consumption since the oil crisis of 1973 is due to more efficient use of energy in homes and offices.  New building technologies, which make lighting, heating, and ventilation systems more efficient, have cut billions of dollars from energy bills in the West.  Since energy savings from these efficiencies save several billion dollars per year today, we can conclude that 50 to 100 years from now they will save more than $200 billion per year (calculated in current dollars).

On which one of the following assumptions does the argument rely?

(A) Technology used to make buildings energy efficient will not become prohibitively expensive over the next century.
(B) Another oil crisis will occur in the next 50 to 100 years.
(C) Buildings will gradually become a less important consumer of energy than transportation.
(D) Energy bills in the West will be $200 billion lower in the next 50 to 100 years.
(E) Energy-efficient technologies based on new scientific principles will be introduced in the next 50 to 100 years.

It was between A and E. 
Thought something different and screwed.

What is the assumption that leads to such a conclusion that more than $200 billion per year (calculated in current dollars) will be saved 50-100 from now? 
Highlighted text is the key to passage. 
- Is it NEW BUILDING technologies or new BUILDING TECHNOLOGIES? Of course latter. This is not much of a hindrance - may be overthinking, how let's see later. 
- The other problem is how a quantifies value of $200 Billions is reached.

So, even if new technologies are not introduced we can still say this much can be saved. Hence it is not necessary that such a thing needs to happen for such a conclusion.
Then what might be case. Since New building technologies help save billions, new buildings must be constructed over these many years. If not built saving such a huge amount would be difficult to achieve. Is it that older ones are being refurbished with new technologies? If not then A is not the answer. Thus, new buildings are required to be built so that such amount is saved over that period. Therefore the assumption is new buildings are being constructed at reasonably good pace.

If yes, then certainly A is the answer. If technologies do become expensive then it acts as a hindrance to reach such a conclusion.

peehu24 · Answer

Even I for one got this question wrong but as I analyze option (A) it becomes explicit that this answer is very much suitable to the question asked. 
If we focus on the last line of the passage, it talks very clearly of SAVING MONEY and that is the ULTIMATE GOAL AND CONCLUSION. 
This boils down the answer to either option (A) or option (D).

If we draw attention towards the last line of the passage again, we will find that it mentions saving energy and as a result, money from the ABOVE MENTIONED EFFICIENCIES. However, option (D) doesn't revolve around ANY OF THESE and is thus, an isolated option.

However, if the technology used to make buildings becomes expensive, will we be able to save money? A negligible amount, at the most. The technology falls under the purview of the mentioned efficiencies and the options also talks about saving money.
And this for me, makes option (A) the perfect option.

Hope this helps!

VerbalBot · Answer

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In Western economies, more energy is used to operate buildings

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