Residential use of wood accounts for approximately 9 PJ of primary energy in NZ. Households also consume about 45 PJ of electricity. Compare the cost of heating a house in $/kWh using: (a) a conventional fan heater, buying electricity at 30c/kWh (b) a heat pump with a coefficient of performance of 2.8 (c) a combustion stove with an efficiency of 90%, assuming that loose firewood can be bought at $290 for 2m3 on TradeMe. Assume that the actual volume of wood is 41% of the loose volume, and that the density of the wood is 431 kg/m3 and the wood has a calorific value of 4.32 kWh/kg.

Residential use of wood accounts for approximately 9 PJ of primary energy in NZ. Households also consume about 45 PJ of electricity. Compare the cost of heating a house in $/kWh using: (a) a conventional fan heater, buying electricity at 30c/kWh (b) a heat pump with a coefficient of performance of 2.8 (c) a combustion stove with an efficiency of 90%, assuming that loose firewood can be bought at $290 for 2m3 on TradeMe. Assume that the actual volume of wood is 41% of the loose volume, and that the density of the wood is 431 kg/m3 and the wood has a calorific value of 4.32 kWh/kg.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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