This topic contains a solution. Click here to go to the answer

Author Question: It is impossible to use appropriate run-of-stream turbines to capture tidal energy. What will be ... (Read 90 times)

ahriuashd

  • Hero Member
  • *****
  • Posts: 535
It is impossible to use appropriate run-of-stream turbines to capture tidal energy.
 
  What will be an ideal response?

Question 2

In 1987, the best refrigerator being sold used 515 kWh/yr and the average used 979 kWh/yr. How much money would have been saved on your electric bill between then and 2000 by buying the more efficient one?
 
  What will be an ideal response?



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

zhanghao

  • Sr. Member
  • ****
  • Posts: 316
Answer to Question 1

There are relatively inexpensive models sold by Chinese companies. Also, new
technologies such as the Davis and Gorlov turbines, hold promise of more efficient but
inexpensive run-of-the-stream devices.

Answer to Question 2

We are not given information about the cost of the two refrigerators, but
(amazingly enough) many times the cost is not significantly different between different
models. Assume they cost the same amount. Then, over 13 years, the cost of the more
efficient model is,
(13 years) x (515 kWh/yr) x 0.10/kWh = (13 years) x 51.50/yr = 669.50
The cost of the average model is
(13 years) x (979 kWh/yr) x 0.10/kWh = (13 years) x 97.90/yr = 1272.70
You would have saved 1272.70 - 669.50 = 603.20 over those 13 years. It is extremely
unlikely that the more efficient could have cost that much more than the average model.
In any case, if the more efficient model is more expensive than the average model, you
would just subtract the extra cost from the savings listed above to find the actual savings.
Over the 19 yr mean refrigerator lifetime, the more efficient model would actually save
881.60 (minus the cost differential, if any) at an electricity cost of 0.10/kWh. If the
electricity cost were just 0.08/kWh, the net savings would be proportionally smaller,
705.28 over the 19 years, 482.56 over 13 years.




ahriuashd

  • Member
  • Posts: 535
Reply 2 on: Jul 28, 2018
Gracias!


nyrave

  • Member
  • Posts: 344
Reply 3 on: Yesterday
Wow, this really help

 

Did you know?

Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.

Did you know?

Certain topical medications such as clotrimazole and betamethasone are not approved for use in children younger than 12 years of age. They must be used very cautiously, as directed by a doctor, to treat any child. Children have a much greater response to topical steroid medications.

Did you know?

Once thought to have neurofibromatosis, Joseph Merrick (also known as "the elephant man") is now, in retrospect, thought by clinical experts to have had Proteus syndrome. This endocrine disease causes continued and abnormal growth of the bones, muscles, skin, and so on and can become completely debilitating with severe deformities occurring anywhere on the body.

Did you know?

Your chance of developing a kidney stone is 1 in 10. In recent years, approximately 3.7 million people in the United States were diagnosed with a kidney disease.

Did you know?

The most common childhood diseases include croup, chickenpox, ear infections, flu, pneumonia, ringworm, respiratory syncytial virus, scabies, head lice, and asthma.

For a complete list of videos, visit our video library