L8 & 9 - Marine Renewables Flashcards
What was the main aim of studying marine renewables?
To determine Resource Potential
What are the 2 current issues in the UK with regards to energy?
- Climate Change
2. Energy Security
By 2020, the UK is aiming to have how much energy from renewables?
30%
How much energy is the UK aiming to get from offshore renewables?
200 mW
When were the 2 most recent UK Climate Change Bills?
2008 and 2012
Where are the legal requirements for Wales and renewables set out?
Government of Wales Act 1998 Section 21
In what year were reductions made to electricity tariffs?
2015
Name the 3 parties involved with trading electricity
- Producer
- Middle Man
- National Grid
By which year will all coal power stations in the UK be removed?
2025
Why do we need to forecast energy?
To know if it can be supplied
What are the 3 main renewable energy sources?
- Wind
- Wave
- Tidal
What are the 2 main energy sources from tidal energy?
- Tidal Current
2. Tidal Head
What is an energy unit?
Joule and Joules/Second = Watt
What are the 2 types of energy?
- Kinetic
2. Potential
What is Kinetic Energy a function of?
Velocity
What is Potential Energy a function of?
Height
What is technology currently best for?
Wind Energy
What is the most powerful energy source?
Wave
Who produces the Marine Renewable Atlas?
ABPMer
What is wind strength related to?
Isobaric Spacing
Where are the most reliable winds?
Sub-Tropics
We’re are the most powerful winds?
Mid-Latitudes
By how much does wind energy decrease overland and why?
50% because of Friction
How much more wind energy is there offshore than onshore?
20-30% more
What is the starting speed required for wind turbines?
4-5m/s
What is the maximum power for a wind turbine?
15m/s (30 knots)
What is the maximum efficiency of a wind turbine?
60%
At what wind speed do wind turbines switch off?
~40 knots
What does wave energy depend on?
Speed and Wave Height
What is the average power of a North Sea wave?
20kw/m
Wave energy is lost to what 2 things?
- Friction
2. Work
Wave energy has the potential to provide how much of the UK’s energy demands?
25%
How efficient are wave conversion devices?
20-40%
Where are the 2 best locations in the UK for wave energy?
- Cornwall
2. Scotland
Give an example of a location whereby Topography has enhanced the local tidal range?
Strangford Loch, Northern Ireland
What is the tidal range of the Severn Estuary?
10-12m
The Severn Estuary has the potential to provide how much of the UK’s energy demands?
5-7%
Who is responsible in the UK for producing tidal predictions?
UKHO
What type of energy is the head of the water?
Potential
What type of energy are tidal currents and potentially how much of the UK’s energy demands could be met from them?
Kinetic
20%
What speed to tidal currents need to be in-order to be viable?
2-3m/s (4-6 knots)
Give 4 examples of projects in place for energy generation
- Limpet
- Pelamis
- Wave Dragon
- Wave Hub
Give 5 things that can be obtained from assessing and modelling renewable energy
- Resource Potential Maps
- Through Life Forecasting Support
- Forecasted Power Production
- Minium and Peak Values
- Daily Forecasts on Power Production
What has the crown estate created for assessing and modelling renewable energy?
A wave and tidal knowledge network
What are the 3 data types you can get for assessing and modelling wind energy?
- Wind Roses
- Maximum/Minimum Values
- Frequency Distributions
Name 2 companies that provide services for assessing and modelling renewable energy
- StormGeo
2. Fugro EMU
What is the forecasting service used by the Met Office?
MetMast
How much energy is available in Wales from wave and tidal resources and how much is extractable?
40 Gw
10% Extractable
What is the EU obligation for renewable energy by 2020 and what is the current state of play in the UK?
To have 15% of energy from renewables, currently
Which type of energy could meet 100% of Wales’ energy needs?
Tidal
What are the 2 forms of Tidal Energy (With Descriptions)?
- Tidal Stream (Impounds High Tide Level Water)
2. Tidal Range (Extract KE from Horizontal Currents through Turbines)
Give 3 examples of tidal energy across the world
- Barrage de La Rance, France
- Annapolis Royal Generating Station, Canada
- Lake Sihwa, South Korea
How much of the UK’s energy could a barrage on the Severn provide?
5%
How much would a barrage on the Severn cost?
~£25 billion
What were the original 2 drivers for the Severn barrage?
- Flood Protection
2. Recreation
How would the severn barrage +vely and -vely impact biodiversity?
-ve: loss of intertidal habitats
+ve: reduced turbidity, increased light penetration and increased primary productivity
What are the 4 operational stages to a tidal lagoon?
- Build up head inside the lagoon by water level falling outside from high to low tide
- Generate electricity by emptying lagoon from HW to LW level
- Build up head outside the lagoon by water level rising inside from low to high tide
- Generate electricity by filling lagoon from LW to HW level
Give 6 facts about the Proposed Swansea Tidal Lagoon
- 9.5km long
- 400 Gwh net annual output
- Electricity for 12,000 homes
- 50-100 year life span
- Generates on the flood and ebb tide for 14 hours/day
- Education, Sports and Art Amenity
Give 3 facts about Tidal Lagoons in North Wales
- High Tidal Range
- Flood Defence Potential
- Electricity Grid Connection Available
Where are the 3 potential sites for tidal stream energy in Wales?
- Bristol Channel
- Anglesey
- Pembrokeshire
What was used to collect data in Ramsey Sound?
2 Side Mounted Vessel ADCPs
What type of flow is preferred by tidal turbines?
Uniform Flow
