# EGEE - Dave has a home in Pittsburgh PA(HDD = 6,000 with a...

This preview shows pages 1–2. Sign up to view the full content.

Dave has a home in Pittsburgh, PA (HDD = 6,000) with a roof area of 1894 ft2. He is considering upgrading the insulation from R-16 to R-28. The estimate for this job from the contractor is \$902. Dave's home is heated with natural gas. Last year, the average price he paid for natural gas was \$14.1/MCF. Assuming an AFUE of 87.5%, how long will it take Dave to recover his investment (in years)? Correct B ) 7.7 Years Cost of insulation = 902 / 1894 = 0.4762 \$/sq.ft Cost of energy = 14.1 / 1,000,000 = 0.0000141 \$/BTU Time to recover investment = (0.4762 x 16 x 28 x 0.875) / (0.0000141 x (28 - 16) x 6000 x 24) = 7.66 yrs A house in State College, PA (HDD=6000) has 344 ft2 of windows with R value = 2.5, 1804 ft2 of walls with R value = 18, and 1101 ft2 of roof with an R-value = 28. What is the total heat loss from the house for the season (in BTUs)? Correct Answer: C ) 39908685.71 BTUs Heat lost through windows = 344 x 6000 x 24 / 2.5 = 3302400 BTUs Heat lost through walls = 1804 x 6000 x 24 / 18 = 2405333.33333333 BTUs

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 4

EGEE - Dave has a home in Pittsburgh PA(HDD = 6,000 with a...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online