Energy Resources and Utilization ME436

2016

Lecture 1b : Introduction

2Lecture 1b : Introduction

Units of Energy • Joule = 1 N – m • K J = J Kilo• M J = J Mega• GJ = J Giga• TJ = J Tera• PJ = J Peta• EJ = J Exa

Energy Resources and Utilization

3Lecture 1b : Introduction

Present Day Energy Usage • Energy usage by end user (us!)

• e.g. energy from burning coal, is reached to us in from of electricity…

• Primary energy and delivered energy

• Primary energy usage of all forms: 502 EJ or 12 000 million tonnes of oil equivalent (Mtoe) (energy usage increased by tenfold during 20th century)

• Fossil fuel contributed to four fifth of total.

Energy Resources and Utilization

4Lecture 1b : Introduction

Present Day Energy Usage

Energy Resources and Utilization

1 year = 24 * 365 = 8760 hours1 Wh = 3600 J as 1 h = 3600 Seconds1 W = 1 N-m/s

5Lecture 1b : Introduction

• World population in 2009 was 6.8 billion

• Average energy consumption per person : 74 GJ

• Equivalent to 5.5 liters of oil per day for every man, woman and child

• North American : 250 GJ per year, Europe : 125 GJ and in poor countries less than one fifth

Energy Resources and Utilization

6Lecture 1b : Introduction

Contribution of Renewable Energies• Traditional biomass, hydro power and other renewable : 13% in 2009

• Largest contribution is from traditional biomass (wood, straw, dung etc)

• Straw :  is an agricultural by-product, the dry stalks of cereal plants, after the grain and chaff have been removed. Straw makes up about half of the yield of cereal crops such as barley, oats, rice, rye and wheat. It has many uses, including fuel, livestock bedding and fodder, thatching and basket-making.

• Thatching is the craft of building a roof with dry vegetation such as straw

Energy Resources and Utilization

7Lecture 1b : Introduction Energy Resources and Utilization

Thatching Bundles of rice straw

8Lecture 1b : Introduction

Contribution of Renewable Energies

Energy Resources and Utilization