# Presentation: 235606

## Progress in U.S. Photovoltaics:Looking Back 30 Years and Looking Ahead 20

**Thomas Surek**
**National Renewable Energy Laboratory**
**Golden, Colorado, U.S.A.**

**Office of Energy Efficiency****and Renewable Energy**

**National Center for****Photovoltaics**

## May 14, 1973

**May 14, 1973**

## 
Major trends

Highlights
Programmatic
Research
Technology
Markets

**Looking Back 30Years**

**Major trends**
**Highlights**
**Programmatic**
**Research**
**Technology**
**Markets**

## Slide 4

## “Champion” cells• 35% concentrator• 25% crystalline silicon• 19% thin films

- Efficiency (%)

- University
-  of Maine

- Boeing

- Boeing

- Boeing

- Boeing

- ARCO

- NREL

- Boeing

- Euro-
- CIS

- 12

- 8

- 4

- 0

- 2000

- 1995

- 1990

- 1985

- 1980

- 1975

- United Solar

- 16

- 20

- 24

- 28

- 32

- 

- 

- 

- 

- 

- 

-       NREL/
- Spectrolab

- NREL

- NREL

- Japan
- Energy

- Spire

- North
- Carolina
- State University

- 

- Varian

- RCA

- Solarex

- UNSW

- UNSW

- ARCO

- UNSW

- UNSW

- UNSW

- Spire

- Stanford

- Westing-
- house

- UNSW

- Georgia Tech

- Georgia Tech

- Sharp

- Solarex

- Astro-
- Power

- NREL

- AstroPower

- 

-  Spectrolab

- NREL

- Emerging PV

*Masushita*

*Monosolar*

*Kodak*

*Kodak*

*AMETEK*

*Photon*
*Energy*

*Univ.S.*
*Florida*

*NREL*

*NREL*

*NREL*

*Princeton *

*U. Konstanz*

*U.California*
*Berkeley*

- Organic Cells

*NREL*

- NREL
- Cu(In,Ga)Se2
- 14x Concentration

- 

***“******Champion” cells******• *****35% concentrator****• 25% crystalline silicon****• 19% thin films**
***Commercial modules******• *****Typically only 50-65% of these values**

## PV Manufacturing R&D Cost/Capacity(DOE/U.S. Industry Partnership)

## PV Module Production Experience (or “Learning”) Curve

**PV Module Production Experience (or “Learning”) Curve**

## World PV Cell/Module Production (MW)

- Source:* PV News*, March 2003

## DOE PV Program Budget History(by Fiscal Year)

- 0

- 20

- 40

- 60

- 80

- 100

- 120

- 140

- 160

- 1975

- 1978

- 1981

- 1984

- 1987

- 1990

- 1993

- 1996

- 1999

- 2002

- Fiscal year

- Current year funding ($ million)

- Proposed

**1973–1983: Decade of **
**Great Expectations**

**1983–1993: Decade of**
**Solid Research Progress**

**1993–2003: Decade of**
**Recognizing PV’s Value**

## 1973–1983: Decade of Great Expectations(and False Promises)

## Slide 11

## 1983–1993: Decade of Solid Research Progress(but Who Needs PV?)

**U.S. Program**
- Long-term, high-risk R&D with funding at a fraction of 1981

## Slide 13

## 1993-2003: Decade of Recognizing PV’s Value(and Paying for It with Subsidies)

**U.S. Program**
- Balanced program of fundamental and applied research, technology development, and some market facilitation; focus on thin-film technologies and manufacturing R&D
- Program plans aligned with U.S. PV Industry Roadmap to 2020

**Research**
- Near 25% efficiency in crystalline silicon and high-efficiency processing (UNSW); rapid thermal processing (Georgia Tech)
- Record efficiencies in CIGS (19.2%, NREL); CdTe (16.5%, NREL)
- Three-junction GaInP2/GaAs/Ge cell with >35% efficiency at up to 400 suns (Spectrolab)
- New PV technologies emerging (dye-sensitized cells, organic and polymer cells, nanostructures)
- Improved fundamental understanding of materials, devices, and processes – but there is still a long way to go

## 1993-2003 (continued)

Technology
Rapid expansion of both ingot-based and ribbon-based silicon technologies worldwide (some >100 MW)
First-time manufacturing of thin films (few MW to few tens of MW) and concentrators (up to MW)
Many corporate turnovers resulting from manufacturing, reliability, and marketing issues for thin films

**Technology**
- Rapid expansion of both ingot-based and ribbon-based silicon technologies worldwide (some >100 MW)
- First-time manufacturing of thin films (few MW to few tens of MW) and concentrators (up to MW)
- Many corporate turnovers resulting from manufacturing, reliability, and marketing issues for thin films

**Markets**
- Average growth rate of >30% worldwide over last 5 years
- Cumulative worldwide: >1000 MW in 1999, >2000 MW in 2002
- Large market-incentive programs (i.e., subsidies, policies) in Europe and Japan; some State (and some Federal) incentives in U.S.
- Focus on residential/commercial buildings; some utility systems
- Installed system costs decreased, but trend slowed in recent years
- Applications in developing countries continue to thrive

## Looking Ahead 20 Years

## “Disclaimer”
Three scenarios:
Pragmatic (and realistic)
Optimistic (but probable)
“Wishful thinking”
Technology projections:
Balance of systems
Crystalline silicon
Thin films
Concentrators
New technologies

**“****Disclaimer”**
**Three scenarios:**
**Pragmatic (and realistic)**
**Optimistic (but probable)**
**“****Wishful thinking”**
**Technology projections:**
**Balance of systems**
**Crystalline silicon**
**Thin films**
**Concentrators**
**New technologies**

**Looking Ahead 20 Years**

## Projections for Balance-of-Systems Costs

**Future**
- Costs will continue to decline for both area-related (e.g., installation) and power-related (e.g., inverter) BOS with:
- Large-volumes and repetitive applications
- Standardized system designs and components; certification
- Large-volume manufacturing of power-conditioning components
- Engineering improved reliability
- Training and certification of installers
- Total BOS costs of <$1/watt and potentially <$0.50/watt should be achievable in the next decade
- BOS issues are _not_ the “showstoppers” for large-scale PV applications and markets – PV module price and performance can be the limiting factors

**Today**
- High for “one-of-a-kind” and off-grid installations
- Less for repetitive applications (e.g., 1/3 of installed system cost for residential systems in Japan today)
- Some problems with power conditioning equipment, but reliable with good system design, proper component selection, and volume applications

## Projections for Crystalline Silicon...The pragmatic (and realistic) scenario

- Technology will continue to dominate markets for next decade and probably longer
- Silicon “feedstock” will _not_ be a problem; there will be sufficient high-quality silicon available at reasonably low cost
- Efforts to reduce silicon use (thinner wafers) will succeed to some extent
- Research to increase module efficiencies will be key to progress
- For a given cell/module process, need to use wafer resulting in highest efficiency (not necessarily the “cheapest” wafer)
- For a given wafer technology, need cell/module processes resulting in highest efficiency (not necessarily the “cheapest” process)
- There will be cost/efficiency trade-offs to consider

## A Simple View of Module Efficiency Impacts

**A Simple View of Module Efficiency Impacts**

**Equating manufacturing costs*: ****W****low****/W****hi ****= 1 -  (1 – ********low****/********hi****) (1 + C + M)**** **

**Typical values: C = 0.6 to 1.2 and M = 1 to 2, with C + M ******** 2 **

**Examples: ********low**** = 8% and ********hi ****= 12%****	****	**** ****W****low****/W****hi ****= 0**
**	********low**** = 10% and ********hi ****= 12%****	**** ****W****low****/W****hi ****= 1/2**
******low**** = 9% and ********hi**** = 13%****	**** ****W****low****/W****hi ****= 1/13**

***Note: This analysis ignores the significant impacts of module efficiency on system cost.**

## Projections for Crystalline Silicon...The pragmatic (and realistic) scenario

- Technology will continue to dominate markets for next decade and probably longer
- Silicon “feedstock” will _not_ be a problem; there will be sufficient high-quality silicon available at reasonably low cost
- Efforts to reduce silicon use (thinner wafers) will succeed to some extent
- Research to increase module efficiencies will be key to progress
- For a given cell/module process, need to use wafer resulting in highest efficiency (not necessarily the “cheapest” wafer)
- For a given wafer technology, need cell/module processes resulting in highest efficiency (not necessarily the “cheapest” process)
- There will be cost/efficiency trade-offs to consider

- While module price will continue to decrease, it is not likely to follow the “80% learning curve”.  Rather, it will decrease asymptotically to some value (my guess: >$1.20/watt [$2002])
- In this scenario, PV will have a huge, sustainable market, albeit not energy significant until beyond 2050
- Market incentives (e.g., buy-downs, tax credits, regulatory and policy incentives) will enhance market growth, particularly in near term

## PV Module Production Experience (or “Learning”) Curve

**PV Module Production Experience (or “Learning”) Curve**
**... ****The pragmatic (and realistic) scenario**

**1976**

**2002**

**90%**

**80%**

**70%**

**Based on continued progress in**
**and dominance of crystalline**
**silicon technology**

**2013*******

**2023*******

*** ****Future-year markers are based**
** ****on 25% annual growth rates**
**(expect <25% in this scenario)**

## Projections for Thin Films and Concentrators...The optimistic (but probable ) scenario

- Critical technical issues will be resolved with further research
- Thin films: module efficiency, manufacturing scale up, yield and throughput, reliability
- Concentrators: high-efficiency cells and optical components, manufacturing scale up, reliability
- Technologies will gradually gain market share, especially during the latter part of the decade and into the next decade
- Technologies with “niche” market opportunities will have significant early market advantages (e.g., flexible or semi-transparent thin films for building integration)
- Commitment and “deep pocket” investors are key to success
- Materials availability and environmental issues will _not_ be a problem for thin-film technologies
- Education and early recognition/addressing issues are key

- Technologies can significantly impact module price “learning curve”, especially with large-scale manufacturing
- In this scenario, PV will have huge, sustainable markets, and energy significance by 2030
- Market incentives should not be necessary, particularly into the next decade, but large-scale concentrator systems may require regulatory incentives

## PV Module Production Experience (or “Learning”) Curve

**PV Module Production Experience (or “Learning”) Curve**
**... ****The optimistic (but probable) scenario**

**1976**

**2002**

**90%**

**80%**

**70%**

**Based on successful progress **
**in thin films and/or **
**concentrator technologies**

**2013*******

**2023*******

*** ****Future-year markers are based**
** ****on 25% annual growth rates**
**(expect >25% in this scenario)**

## Projections for New Technologies...The “wishful thinking” scenario

- Ongoing exploratory research on future, “third” generation PV technologies is important and will have significant benefits
- Better fundamental understanding of limitations to current (e.g., silicon) and next generation technologies (e.g., thin films and concentrators)
- Potential for discovery of new materials, new devices, new processing, and new physics
- Potential for “breakthroughs” in cost and efficiency
- Many examples of research activities: e.g.,
- High Performance Photovoltaics program at NREL: high-efficiency
- 	multijunction thin films and concentrator cells
- Organic and polymer solar cells
- Nanostructures, quantum dots, and defect-layer solar cells
- Very high-throughput or very low-cost manufacturing processes

- Technologies can significantly impact module price “learning curve”, but this is not likely to happen until past 2020 (my view)
- The “success” of PV does not require these ultimate discoveries – but scientific research and discovery are the foundations for technological progress

## PV Module Production Experience (or “Learning”) Curve

**PV Module Production Experience (or “Learning”) Curve**
**... ****The “wishful thinking” scenario**

**1976**

**2002**

**90%**

**80%**

**70%**

**Based on discovery and **
**progress in new technologies**

**2013*******

**2023*******

*** ****Future-year markers are based**
** ****on 25% annual growth rates**
**(expect >>25% in this scenario)**

## Conclusions

**Conclusions**

**PV technology has made significant progress in just **
**30 short years**
**The same can be expected – and more – in the coming decades**