energy utilization, storage and distribution

Question 1

energy efficiency

Answer 1

the design of a product aims to minimise the energy required to operate the product of a specific period of time

Question 2

Energy conservation

Answer 2

using less to reduce the amount of energy being used

Question 3

What is embodied energy?

Answer 3

assessment of the total energy associated with a product starting from:

• energy required to obtain raw materials
• Energy required to transport the raw materials used in its manufacture
• Energy required used in the manufacture of the product

Question 4

if cradle to grave embodied energy is considered, then you also need to include:

Answer 4

• embodied energy required to operate and maintain the product
• Embodied energy required to dismantle/dispose product

Question 5

Measurements of embodied energy

Answer 5

Mj/kg

kgCO2/kg

Question 6

Replacement of materials with lower embodied energy

Answer 6

where practical, replacement of materials for a product with one with lower embodies energy result in greater conservation of energy but not in all cases

weight is compromised

material property of substituted material may not have the right property

Question 7

Distribution of energy: national and international grid systems

Answer 7

• national systems generates electrical energy to be supplied within a country
• International system allows electricity generated in one country to be supplied and used in another, example Mexico supply electricity to USA

Question 8

Why is AC adopted over DC for power transmission

Answer 8

AC can be readily transformed to higher or lower voltage unlike DC current

Using DC would result in huge transmission losses through a conductor especially the long transmission lines involved

Question 9

Local combined heat and power (CHP)

Answer 9

CHP (also called cogeneration) systems capture the waste heat which is passed through a heat exchanged to heat air or water. Hot water then for example could be supplied to homes or industries

• generation of electricity produces a lot of excess heat which is usually lost to atmosphere

Question 10

Systems for individual energy generation - solar energy

Answer 10

> collected as thermal energy to heat up water/dry items/seasoning of material, etc

> converted into electricity through the us of photovoltaic cells which produce electricity by means of the photoelectric effect

Question 11

what is the photoelectric effect?

Answer 11

It is the release of free electrons from a material when it is exposed to photons of light Solar panels to convert sunlight to electricity

Question 12

Greenhouse effect

Answer 12

• some sunlight that hits earth is reflected back into space, while the rest becomes heat
• Greenhouse gases absorb and reflect heat radiated by earth, preventing it from escaping into space

Question 13

Why is CO2 and other gases more of a concern that water vapour when it comes to greenhouse gas emissions?

Answer 13

Water vapour and cloud formation are not really within human control

Question 14

Global warming potential

Answer 14

• a measure of how destructive an air pollutant is to the environment through its ability to cause global warming. GWP of a pollutant is compared with reference to the damage caused by co2

a certain weight of a GHG can be expressed in terms of its CO2 equivalence by multiplying its weight by the GWP

Question 15

aim of sustainable design

Answer 15

to attain energy efficiency in the final product

Question 16

What features might make a car more energy efficient?

Answer 16

• weight of car
• car body design
• auto light features
• auto start stop features
• cruise control

Question 17

example of conservation of energy

Answer 17

driving less to conserve energy

Question 18

energy storage in batteries

Answer 18

• lithium ion batteries
  > deemed mainly to be non hazardous by gov
  > used in mobile phone
  > can be taken to standard recycling centres

Question 19

how a wet scrub cleans polluted air

Answer 19

1. dirty air from factory enters the scrubber
2. The polluted air passes through a layer of steam. Large particles are trapped inside steam droplets
3. The polluted steam droplets are collected in a filter (mist eliminator)
4. Clean air is released from the scrubber system

International targets for reducing pollution/waste

> target may be different for each country depending on how much CO2 or CO2e they are emitting

Question 20

Problems with setting/implementing international targets for emission

Answer 20

• legislation does not necessarily mean enforcement takes place
• Manufacturers will not want to pay extra to have cleaner technology
• Different countries may not come together for an agreement for reasons such as:

> different countries may be at different stage of development

> funding of clean technology may be a problem for some countries

> attitudes towards the environment may vary

Question 21

Incremental solutions advantages

Answer 21

• use of existing trusted technologies therefore greater certainty of success
• Lesser downtime in production (revenue stream does not need to stop)
• Requires less capital outlay compared to radical change
• Allows company to strategically plan the changes

Question 22

incremental solutions disadvantages

Answer 22

• it may take too long to make final changes
• Small changes may not meet legislation requirement
• Marketplace may get saturated by the time final charge is done

Question 23

radical solutions advantages

Answer 23

• exploration of new technology which may lead to many benefits for consumers and other products
• Creation of new industries and therefor jobs for people
• Fewer competitors as not many companies may have budget or technology to take on radical solution
• Creator of new technology has the chance to patent it resulting on financial benefits as others cannot copy technology

Question 24

radical solutions disadvantages

Answer 24

• costly to invest in new technology and loss of profits during down time, may also need to spend for research and development and also training
• The implementation of radical solution may not be successful exotically if its brand new technology
• Consumers may not be ready to take the risk in investing in the re-engineered product which uses new technology
• There may be many teething problems encountered during and after development of radical change

Question 25

systems level solutions

Answer 25

• refer to solutions that address the whole system, not just the components
• These solutions are often regulatory in manner (taxes, tax benefits, legislation, etc.) and may require government intervention as well as cooperation from major corporations/institutions.