chapter 7 - sustainablity

Question 1

what does EFW stand for

Answer 1

energy from waste

Question 2

what does WTE stand for

Answer 2

waste to energy

Question 3

what do EFW and WTE both involve ?

Answer 3

incinerating waste, which means burning it to dispose of it but also to produce useful energy.
the amount of energy recovered depends on the efficiency of the incineration plant

Question 4

what is salvage and what does it involve?

Answer 4

a type of recycling that involves stripping out materials e.g. gold from phones / computers and lead from car batteries
generally carried out where the salvaged materials have high value (gold)

Question 5

what’s biofuel?

Answer 5

a fuel liquid, another form of renewable energy derived from biological materials or biomass (such as dead trees, branches etc)

Question 6

what effect do solar cells use to convert the suns energy into electricity?

Answer 6

the photovoltaic effect which involved the creation of a voltage due to the cell being directly exposed to the suns radiation

Question 7

wind energy pros (2)

Answer 7

• !doesn’t create greenhouse gases

* long term potential

Question 8

wind energy cons (4)

Answer 8

• high initial instillation costs
• ugly
• noisy
• large amount of land needed

Question 9

solar energy pros (4)

Answer 9

• can be placed out of sight
• once installed all energy is free
• little maintenance
• can be installed along roads + act as noise barrier

Question 10

solar energy cons (3)

Answer 10

• expensive to install
• supply can be reduced by cloud cover
• less useful in countries with less sun

Question 11

biomass pros (1)

Answer 11

•left over parts of food crop can be used

Question 12

biomass cons (3)

Answer 12

• large amount of land required
• not ideally suited for fuel
• burning wood produces soot