Week 7-8 Flashcards
Battery
devices that use an electro-chemical control method to store electricity/ potential E
Portable/motive storage
Are used in primary and rechargeable consumer devices, auxiliary power units APUs), military applications, and transport use (EVs)
Stationary storage
Can be broken down into two categories:
• Customer sited storage: for emergency power, power conditioning (smoothing power), and off grid, remote storage
• Grid storage: supporting function of electricity grid, mostly via pumped hydro storage used to meet peak power and provide ancillary services
Grid storage
supporting function of electricity grid, mostly via pumped hydro storage used to meet peak power and provide ancillary services
Pumped hydro
o Gravitational potential energy
o Type of mechanical storage. Water can be pumped to a higher elevation, and stored in some reservoir for later use. When energy is required, the water can be run through a turbine to generate electricity.
Fuel cell
Device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent
Energy density
Ability to store energy per unit of volume
Volume energy density
Ability to store energy per-unit of volume (also volumetric energy)
Specific energy
Amount of energy stored per unit of mass, relevant as material is cost driver. More energy per unit of mass is a form of an efficiency improvement in material usage.
Concept as a function of power
Power density
Ability to store power per-unit of volume
Concept as a function of power
Lifetime
also called cycle life, total number of charge and discharge cycles that can be expected
Cycle
cycles of charge and discharge; count how many times each process occurred for a storage device.
Cycle cost
Cost of a battery cycle for an EV.
o EVs are typically 4 tikes cheaper as ICE vehicles, but less so when you factor in cycle costs. Cycle costs change with electricity prices and battery costs.
LCOS
=Levelized Cost of Storage (LCOS): LCOE for stored electricity
o Capital costs: storage devices is amortized over over useful life of device, taking into account usage patterns
o OM costs: only fixed OM matter; variable OM are subsumed into cycle cost
o Fuel costs: input energy, and embedded cost. This input energy might change by location and time of day
Time Shifting
Moving chunks of energy from the time in which they were generated to another time when they are more valuable. Done via load shifting, day-night arbitrage.
Firming
overcoming the constraint of intermittent energy options by storing this energy such that it is dispatchable
Distributed Generation
relatively new method of producing electricity on the customer’s side rather than producer’s sides of electricity system.
o Advantage: I am foregoing to use the utility (TD and G.)
o Disadvantage: because of Res, intermittency problem, I cannot rely on the rest of system
Experience Curve
Concept that describes the ratio (progress ratio or learning rate) by how prices for a technology decline depending on its cumulative production or sales. Like a learning curve.
• X-axis: cumulative production/sales
• Y-axis: cost/unit
• Slope: negative and stable, has nothing to do with time
• Should use costs, as this reflects scale and technology improvements, but often prices are better accessible
• Time = points on the line. The more the points are spread apart from each other (größere Lücken), the quicker the price comes down
Progress Ratio
PR = 1-LR
o A high LR and lower PR describes a steeper EC
o Nature of technology dictates PR
o Speed of industry growth does not matter for PR
What drives the progress ratio?
o Scale increases
o Technology improves
o Input prices change
Learning Ratio
% drop in the cost to produce the technology for each doubling of cumulative production
Market shakeout
end of price umbrella when prices fall faster than costs to adjust high prices to actually lower cost levels (happens when prices are used instead of costs)
Price umbrella
can happen because of excess D, or when producer of new product uses market power to hold the price at a higher level than necessary
Parity
Point at which DG (PV) is competitive with conventional grid-supplied electricity
Learning Investments
additional costs which will bring a technology to the break-even point (the costs the market currently considers cost efficient)
