emerging technologies

Question 1

what is the ‘theoretical global
potential of ocean energy (OE)

Answer 1

100,000 TWh

Question 2

with todays technology how much of wave and tidal energy is it estimated we can extract

Answer 2

Wave energy – 45,000 TWh / year.
Tidal energy – 2,200 TWh / year

Question 3

How does ROI and NI receive most of there energy

Answer 3

they both are well connected to other nations by interconnectors with NI importing 92% and they both work off a “island of ireland basis”

Question 4

Why can Ireland benefit from wave and tidal

Answer 4

Being an island Ireland have alot of access to OE. Also the west of ireland is sitting right on the gulf stream with strong winds which as known winds create waves

Question 5

how do Ireland exploit tidal energy

Answer 5

In NI – Tidal energy dominates the resource potential with sites across the North East Coast, Copeland Islands and Strangford Lough, offering significant tidal flows that are
capable of hosting tidal devices with an estimated installed capacity of up to 650 MW

Question 6

What is the benefits of exploiting OE in Ireland

Answer 6

1- decrease the dependency on fossil fuels which in turn will save money and lower carbon emmisions
2- Increased energy security, not as concerned in oil price hikes, or
geopolitical conflict in the Middle East / Russia.
3- Additional employment, thousands of highly technical jobs are
going to be made available
4-Potential to export energy, making Ireland a global leader in the OE market both in terms of manufacturing, technical expertise and exporting energy.

Question 7

What is the primary requirement for locating tidal barrage

Answer 7

the primary requirement for locating tidal barrage is tidal range R. This must generally be at least 5m to make a project economically feasible. This fact will rule out many locations, as the value of R cannot be changed

Question 8

what are two issues surrounding tidal in terms of money and time?

Answer 8

1- Capital investment- as these projects are huge raising capital for them is next to impossible as loan rates make it economically unfeasible to do so. This would make the price of electric from these projects very high and uncompetitive to normal
2- Time lag- The construction would take years. The investors would not make
any money until electric is generated. This huge time lag is a major problem for
Tidal Barrage projects

Question 9

what are two issues surrounding tidal in terms of grid and other sources of electricity?

Answer 9

1-The huge Power created by the barrage plants put a
huge demand on the nearby National Grid. Serious upgrades will be required,
and these would have to be paid by the project investors, and are anticipated to
add some 10% to the project costs.
2-the ratio of output from a tidal barrage to a nuclear power plant is much lower.
Tidal-0.23
nuclear 0.77
making a project possibly unsustainable to meet demand

Question 10

what are two issues surrounding tidal in terms of water and blade length?

Answer 10

1- the required tidal seeds occur 40-50 m in depth. with 70% of energy is in the upper depth of water making it limited for the blade length
2- – Mean peak spring tidal currents of at least 2 to 2.5
m/s and at a depth of between 20 and 35 metres are necessary to
make the projects economically viable. As water velocities are greater
when the tidal movements are concentrated by passing through
channels, or around Islands, head lands, their position is generally
limited to these locations

Question 11

What are the two types of tidal energy systems?

Answer 11

1- Tidal barrage generators
2- tidal stream generators

Question 12

How does a tidal barrage work?

Answer 12

These involve letting the tide come in, and using a tidal barrage to run the water through turbines, which turn to produce
electricity.

Question 13

What are the three types of tidal barrage generators

Answer 13

1-Ebb generation
2-Flood generation
3-2 way generation

Question 14

How does ebb generation work

Answer 14

Water is allowed to flow freely through the barrage from the sea to the basin.
Then it is trapped, and the sea level falls to nearly low level. Now the tidal
range at almost max value, the valves are opened and power is generated as
the trapped water flows through and back to sea.

Question 15

Give 2 advantages and 2 disadvantages of ebb generation and flood generation

Answer 15

Advantages;
1-Large power output when operational.
2-Simplistic turbines used which are cheaper and easier to maintain.
Disadvantages;
1-There is only power output for approx. 3 hours to 6 hours and hence there are large periods with no power output.
2-This makes it a hugely intermittent energy source, and will the power times
match demand?

Question 16

how does flood generation work

Answer 16

Complete opposite to Ebb Generation. Here water is trapped at high level at
the sea side of the barrage. Then, when the basin water level is near minimal,
the valves are opened, and then water flows in to flood the basin, generating
electricity.

Question 17

How does 2 way generation work?

Answer 17

electricity is generated as the water ebbs out to sea, and when the
water comes in to flood the basin.

Question 18

give three advantages and two disadvantages off 2 way generation

Answer 18

Advantages;
1- Power is produced for a longer duration.
2-Smoother power output.
3-Increased likelihood of power meeting demand.
Disadvantages.
1-Reduced maximum power output.
2-More complex turbines used, which are more costly to purchase and maintain.

Question 19

give one variable that would affect the output of a tidal barrage

Answer 19

P ∝ R2
power output is directly proportional to tidal range sqaured

Question 20

Give 2 examples of tidal barrages

Answer 20

Rance estuary, france

Question 21

How do tidal stream generators work

Answer 21

Sometimes referred to as Tidal Current systems. These work much like a wind
turbine under water

Question 22

what is the minimal speed and depth for tidal stream to operate optimally

Answer 22

mean peak spring tidal currents
of at least 2 to 2.5 m/s and at a depth of between 20 and 35 metres are seen
as necessary for economic exploitation.

Question 23

List some facts about SEAgen in strangford

Answer 23

This project was completed in 2008.
Delivered power to the grid in 2009, first UK Tidal Current machine to receive
ROCs.
Rated at 1.2MW with a water speed of 2.4 m/s.
The turbine blades are some 16m diameter.
Blades can pitch 180 degrees, to facilitate Ebb and Flood generation

Question 24

explain how point absorbers work

Answer 24

Point absorbers have small dimensions relative to the incident wavelength and
work by drawing wave energy form the water beyond their physical dimensions.

Question 25

give an advantage of a point absorber

Answer 25

Being sensitive to waves from all directions, they do not require freedom to
orientate to the incoming waves and so can be tightly moored to the seabed. In
principle they could be extremely thin vertical cylinders which execute large
vertical excursions in response to incident waves, but in practice the hardware
involved means that they are at least a few metres in diameter and absorb
energy from perhaps twice their own width

Question 26

How does attenuator work

Answer 26

Attenuators have their principal axis perpendicular to the wave front, so that
wave energy is gradually drawn in towards the device as the waves move along
it.

Question 27

What operations does the attenuator do

Answer 27

the attenuator needs to always be orientated at 90 degrees to
the wave front, and so a leading buoy and anchor permit the device to swing
around and orientate to the principal wave direction. An array of attenuators
will require sufficient spacing between individual devices to allow them to swing
round on their moorings without fouling their neighbours.

Question 28

what are the 4 environmental impacts of wave energy

Answer 28

marine life and habitat, toxic pollution, visual and noise impact and conflict with other sea users

Question 29

how does wave energy effect the marine life and habitat?

Answer 29

tidal barrage- under water noise and electromagnetic fields disturb the marine life and can cause habitat this is because the land in the tidal range is completely disturbed.
Tidal stream generator- the rotors in the water interfere with the movement of sea creatures and can also kill them in their blades
wave energy- some sea creatures may change the migration patterns to avoid interaction with these devices

Question 30

how does toxic pollution from wave energy have an effect

Answer 30

because the tidal barrage will lie across the path of waters moving sea ward from river mouths, this could result in the contamination off water from chemical run off to the land or also burst pipes or leakes in the equipment could cause sea water pollution

Question 30

how does wave energy have conflict with other sea users

Answer 30

fisher men and other boating companys like ferrys will be affected as all these generators and equipment may stop wild life from coming down stream and could affect the migration patterns. also the ferrys may need to take longer routes to avoid crashing into these devices

Question 31

Define what is meant by a smart material

Answer 31

Smart Materials – A term used to refer to a range of materials which have the ability to alter their basic
physical properties when an external influence such as temperature, light level, pressure or electricity changes.

Question 32

Name 5 types of smart materials

Answer 32

 Smart Glass.
 Self-Cleansing glass
 Shape memory alloys (e.g frames for glasses).
 Windows that produce electricity
 Self-Healing materials

Question 33

How does smart glass work and how can this be used for environmental purposes

Answer 33

Smart glass and film contain tiny liquid crystals that align with the application of electricity, making the glass look transparent. In the absence of an electrical current these crystals randomly orient and scatter the light, making the glass look milky and opaque.
This can help with alloying natural light in using less lighting for a buildjng while also providing a degree off privacy

Question 34

what is a smart system?

Answer 34

Smart Systems have a wide range of applications, and generally involve the
use of miniaturised devices that incorporate the following 3 main control
functions;
1- sensing
2-actuation
3- controlling

Question 35

Explain what sensing actuation and controlling is in a smart system

Answer 35

 1 - Sensing of changes in the environment being controlled and monitored.
 2 - Actuation of devices in response to the changes identified.
 3 - Controlling the situation taking account of the changing variables in the surrounding environment.

Question 36

why are smart systems useful

Answer 36

Smart systems are simply ‘smart’ as they can react to the a change in the environment themselves, and act upon it they don’t need us to do anything when they are in operation.
saving alot of time and money as external workers are not needed

Question 37

what are the benefits of a smart WASTE system

Answer 37

1- identify peak times of waste
2- can organise disposal when required
3- anticipate need
4- more cost affective
5- better planning of collection of schedules

Question 38

give three ways a smart transport system operates

Answer 38

1-glowing lines- provides light for dark roads
2-dynamic paint- they light up in low temperatures to warn road users of potential black ice
3-interactibe light- these light up dark roads but also save energy when no cars are about

Question 39

give two examples of smart systems in engineering

Answer 39

superconducting metals
nanotechnology

Question 40

what are the economic benefits of a smart system?

Answer 40

health care-– the use of smart systems can lead to improved diagnostic tools and less intrusive operating procedures this will cut down waste on time and pharmaceuticals needed which are manufactured from fossil fuels.
Transportation- there could be an increase in the development of pre-crash systems, more energy efficient devices for mobility e.g. hybrid vehicles and electric traction and the efficient control of traffic movement in our cities
Environmental and waste management – the use of smart systems could lead to more efficient use and control of energy and facilitate the transistion or addition of renewable energy resources into distributed networks such as the National Grid. This
would also allow us to control energy use in the home remotely and economically

Question 41

what are the econmical benefits of smart systems?

Answer 41

health care- with improved diagnostics and less intensive surgical procedures we save time and money on the likes of needing to purchase new equipment and will not need as much pharmacuticals like anastetic which also saves money through not needing to min as much fossil fuels.
transportation- with new smart motorways, electric vehicles. smart motor ways save money as not as much traffic build up which will save people deseil and less money spent of oil, electric vehicles save alot of people money on the need for desiel and petrol and oil for engines
environmental and waste management- more efficient energy distrubution will lead to less waste energy and not as much money needing to be sent on energy

Question 42

what are the two biggest contributers of Co2in terms of fossil fuels

Answer 42

natural gas at 47.3% and coal at 28.5%

Question 43

what is carbon capture

Answer 43

the process of trapping carbon dioxide produced by burning fossil fuels or other chemical or biological processes and storing it in such a way that it is unable to affect the atmosphere, with the aim of mitigating the effects of global warming.

Question 44

how can carbon capture control help the environment

Answer 44

by sending 90% of Co2 for sequestration in deep under ground aquifiers it also helps as burning hard coal produces nearly 1000 co2 where as hard coal with ccs is only 200

Question 45

what are the 4 stages of carbon capture

Answer 45

trapping and separating, transport, and storage

Question 46

how does trapping and separating work in carbon capture

Answer 46

Entails taking gas emitted from the process and separating CO2 from the other gases which are present. There are 3 main ways in which this is currently done;
* Post – combustion capture.
* Pre-combustion capture.
* Oxy-fuel combustion capture.
The first 2 as their names imply are carried out at different stages of the combustion process, while oxy-fuel combustion
required the fossil fuel being used and burnt in oxygen

Question 47

how does transport work in carbon capture

Answer 47

Involves moving the isolated CO2 (usually in a liquefied state) to a location for its storage. This is most efficiently done through a system of pipes which transports the CO2 to a dis-used oil well or under the sea.

Question 48

how does storage work in carbon capture

Answer 48

Refers to the ling term location for the captured CO2. As mentioned previously this can be done either underground or underwater

Question 49

give 4 advantages of geo-engineering as
the deliberate modification of the Earth’s atmosphere to offset the effects of
climate change

Answer 49

1- counteract increase global temperature
2-facilitate the control of greenhouse gases
3-counteracts climate change
4-some technologies like cool roof technologies are inexpensive and effective

Question 50

give 4 disadvantages of geo-engineering as
the deliberate modification of the Earth’s atmosphere to offset the effects of
climate change

Answer 50

• Risks associated with control and predictability of technologies and
  processes.
• Little known about the long term side effects.
• Ethical concerns and risks associated with the use of geo-engineering.
• Governance risks.

Question 51

give 4 geo-engineering techniques and how they are applied

Answer 51

Cloud seeding where clouds are injected with crystals to produce ‘rain
on demand.
* Space reflectors which block a proportion of the sun’s rays from entering the earth’s atmosphere thereby reducing global warming
* Afforestation whereby global scale planting of trees absorbs CO2 from the atmosphere
* Biochar, the process of ‘charring’ biomass so that the carbon it contains is locked up in the soil

Question 52

what is the operation of bio- photovoltaic devices (bpv)

Answer 52

Bio-Photovoltaic (BPV) devices generate electricity from light energy by
exploiting the photosynthesis of living organisms such as moss, algae,
cyanobacteria and vascular plants