2. Funded by
• The good news… Growing prospects for RE!
Introduction
⎻ IEA midterm market forecast 2016:
o In 2015 Renewables surpassed coal in
electricity capacity…
o 60% of installed capacity in the next 5
years will be Renewable...
o The share of Renewables will be 28%
by 2021…
4. Funded by
Introduction
• The electricity system
– Electricity cannot be stored in large quantities
– Generation must match the demand at all times
– Continuous and reliable supply 24/7 is needed
Wha
This
con
the
cut
ren
sys
What h
better c
New
15
nat
me
eas
Figure 1: Basic elements of the electricity system
penetra
needs t
share o
controlled in real time, 24 hours a day, to ensure a
reliable and continuous supply of electricity to homes
and businesses.
This diagram below depicts the basic elements of
the electricity system: how it is created at power
generating stations and transported across high-
voltage transmission and lower-voltage distribution
lines to reach homes and businesses. Transformers
at generating stations step the electric voltage up for
efficient transport and then step the voltage down at
substations to efficiently deliver power to customers.
Adequacy: the ability of the electricity system to
supply the aggregate electrical demand and energy
requirements of the end-use customers at all
times, taking scheduled and reasonably expected
unscheduled outages of system elements into
account.
Reliability: the ability of the power system to
withstand sudden disturbances, such as electricity
short circuits or unanticipated loss of system
elements from credible contingencies, while
avoiding uncontrolled cascading blackouts or
damage to equipment.
6. Funded by
A new challenge
• High shares of intermittent renewables
– Demand is some times reached by intermittent plus base
load sources (with no regulation)
• I.e. the more intermittent capacity, the higher
the risk of system imbalance
• Additional ancillary services for balancing the
system are needed:
– Short term power reserve (scheduling and dispatch)
– Spinning reserve (rapid response)
10. Funded by
A new challenge
• The only sustainable solution:
– Dispatchable renewables
• Built-in storage in renewable energy plants
– Mechanical storage (Flywheels)
– Electrical storage (Batteries)
– Thermal storage
• Is this realistic in the short to mid term?
12. Funded by
A new challenge
• Dispatchable renewables:
Dispatchable RENon-Dispatchable RE
The challenge of electricity storage
Mechanical Electrochemical Chemical
Hydro pumping
Flywheels
Compressed air
Batteries Hydrogen
Power-to-gas
Wind & PV
?
Non-dispatchable
Electricity
Generation
STE (CSP)
Hydro,Biomass
& Geothermal
Resource
naturally stored
Resource collected
& thermally stored
in tanks
Dispatchable
Electricity
Generation
Dispatchable
Electricity
Generation
PowerinMW
Time of Day
Figure 3: Different approaches to produce dispatchable electricity from renewable energy technologies.
6
The diagram below shows the different approaches to produce dispatchable electricity from renewable energy
technologies.
All approaches try to deal with the problem – how to
store the electricity and pursue the same objective:
large-scale storage of surplus power using available
technologies in order to avoid the waste of available
laboratory level, has not been implemented at industrial
and large commercial scale. Furthermore, the life
cycle assessment of this solution shows poor results;
eventually, this solution is not competitive, except in
– After a huge deployment
of RES (up to now 400
GW of wind and 200 GW
of PV), is time to face
this essential “problem”.
– CSP is the only
dispatchable renewable
technology with potential
enough to achieve an
almost carbon free
generation system.
13. Funded by
Dispatchable renewables
• How it works?
– Thermal energy is gathered during sunny hours.
– Production can be shifted to higher demand times.
– Round-trip efficiency over 98%
15. Funded by
Dispatchable renewables
• Dispatchable generation example
Wind
PV
CSP
HYDRO
– Mainly Hydro is providing the required
balancing to the electricity system
– Dispatchable CSP plants operating in
“solar driven”. Dispatchabilitynot used.
16. Funded by
Dispatchable renewables
• Dispatchable generation example
– PV installed capacity
~ 4.7 𝐺𝑊
– CSP installed capacity
~ 2.3 𝐺𝑊
– PV contribution in
sunny hours is far
below than double the
CSP one
CSP PV
17. Funded by
Dispatchable renewables
• What about the costs?
– To date, the direct generation costs of CSP are
higher than those of Wind and PV.
– Large cost reduction potential (“Maturity factor”)
• 5 GW of CSP Vs. 200 GW of PV and 400 GW of wind
• PPAs for Noor II & III 15% lower than Noor I (2 years ago)
• A 110 MW STE / PV in Chile with PPA of $110/MWh.
• The tariff in South Africa for the current “round” is 20%
less than the previous one (18 months ago).
18. Funded by
Dispatchable renewables
• What about the costs?
– The higher “costs” of CSP without consideration of its
“value” results in the current small market volume.
– System Value approach is more appropriate
• IEA Next Generation Wind and Solar Power:
“The traditional focus on the levelised cost of electricity (LCOE)
is no longer sufficient. Next-generation approaches need to
factor in the system value (SV) of electricity.”
“SV is defined as the overall benefit arising from the addition of
a wind or solar power generation source to the power system; it
is determined by the interplay of positives and negatives.”
19. Funded by
Dispatchable renewables
• System Value of solar technologies
– NREL: Estimating the Value of Utility-Scale Solar Technologies
in California Under a 40% Renewable Portfolio Standard
STE with storage
value (USD/MWh)
PV value
(USD/MWh)
STE with storage
value (USD/MWh)
PV value
(USD/MWh)
Operational 46,6 31,9 46,2 29,8
Capacity 47,9-60,8 15,2-26,3 49,8-63,1 2,4-17,6
Total 94,6-107 47,1-58,2 96,0-109 32,2-47
33% Renewables 40% Renewables
Value component
– Operational value represents the avoided costs of conventional generation
along the related ancillary services costs as well as savings on emission costs.
– Capacity value reflects the ability to avoid the costs of building new
conventional generation due to growing energy demand or plant retirements.
NREL is a national laboratory of the U.S. Department of Energy
Office of Energy Efficiency & Renewable Energy
Operated by the Alliance for Sustainable Energy, LLC
This report is available at no cost from the National Renewable Energy
Laboratory (NREL) at www.nrel.gov/publications.
Contract No. DE-AC36-08GO28308
Estimating the Value of Utility-
Scale Solar Technologies in
California Under a 40%
Renewable Portfolio Standard
J. Jorgenson, P. Denholm, and M. Mehos
Technical Report
NREL/TP-6A20-61685
May 2014
20. Funded by
Dispatchable renewables
• Cost and Value of dispatchable CSP
ONSHORE WIND AND PV
COMPETITIVE COST LEVE
Current
gap
14 c€/kWh
6 c€/kWh
STE
5 GW
Wind
400 GW
PV
200 GW
Value
Maturity
The PPAs for the two recently awarded STE plants in Moroc
15% lower than the previous one for Noor 1 awarded 2 yea
EUROPEAN SOLAR THERMAL ELECTRICITY ASSOCIATION
Required value for a 25-year PPA without escalation for a standard 150
MW 5-hour storage STE plant without any kind of financial public support
Source ESTELA
Stars reflect the PPA harmonized – disccounting
the differences with the “standard” plant – values
of real projects in different countries
• Strategic targets for CSP:
– More than 40% cost
reduction by 2020
– Objective price: < 10 c€/kWh
(with DNI > 2000
kWh/m2·year)
• Key challenge:
– Getting political “investment drivers”
to look at the difference between CSP
costs and CSP value
22. Funded by
Conclusions
• The good news: CSP can and will help deploy
cheap variable RES
– CSP is – and will continue to be – the necessary
choice when developing a power system in sunny
countries in which new capacities are needed.
– CSP should be the preferred choice for policy
makers that, unlike investors, should duly
integrate in their decision process all the technical
and economical impacts of this technology.
23. Funded by
Conclusions
• The optimum solution:
– A well balanced electricity generation mix
– Intermittent sources to lower the direct cost
– Dispatchable CSP to provide stability and reliability
• ANDASOL plants (150
MW) and wind parks
(200 MW) in the
province of Granada,
Spain.
