BB test 5 section 2

GRE Verbal Problem Solving
1

The use of heat pumps has been held back largely by skepticism about advertisers’ claims that heat pumps can provide as many as two units of thermal energy for each unit of electrical energy used, thus apparently contradiction the principle of energy conservation.

I cannot understand the advertisers’ claim.

Besides, I thought that using heat pumps has been avoided because people do not believe the advertisers’ claims. But it seems that people do not use them based on advertisers’ claims.
How can I interpret “skepticism about”?

2

Hi @hylee425

From what you have mentioned it seems that the Advertisers’s claim is that heat pumps can produce energy output that is twice the energy input.

The first sentence says “held back by skepticism” meaning people are restraining themselves from using heat pumps because they are not convinced / doubtful (skeptical) of the aforementioned claim.

Hope this helps.
Jeet