1. The Post CSI World in California: A Vertically Integrated Manufacturer’s PerspectiveSachu Constantine September 16, 2010

2. 2 Safe Harbor Statement This presentation contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements are statements that do not represent historical facts and may be based on underlying assumptions. SunPower uses words and phrases such as "expects," “believes,” “plans,” “anticipates,” "continue," "growing," "will," to identify forward-looking statements in this presentation, including forward-looking statements regarding: (a) plans and expectations regarding the company’s cost reduction roadmap, (b) cell manufacturing ramp plan, (c) financial forecasts, (d) future government award funding, (e) future solar and traditional electricity rates, and (f) trends and growth in the solar industry. Such forward-looking statements are based on information available to the company as of the date of this release and involve a number of risks and uncertainties, some beyond the company's control, that could cause actual results to differ materially from those anticipated by these forward-looking statements, including risks and uncertainties such as: (i) the company's ability to obtain and maintain an adequate supply of raw materials and components, as well as the price it pays for such; (ii) general business and economic conditions, including seasonality of the industry; (iii) growth trends in the solar power industry; (iv) the continuation of governmental and related economic incentives promoting the use of solar power; (v) the improved availability of third-party financing arrangements for the company's customers; (vi) construction difficulties or potential delays, including permitting and transmission access and upgrades; (vii) the company's ability to ramp new production lines and realize expected manufacturing efficiencies; (viii) manufacturing difficulties that could arise; (ix) the success of the company's ongoing research and development efforts to compete with other companies and competing technologies; and (x) other risks described in the company's Annual Report on Form 10-K for the year ended January 3, 2010, and other filings with the Securities and Exchange Commission. These forward-looking statements should not be relied upon as representing the company's views as of any subsequent date, and the company is under no obligation to, and expressly disclaims any responsibility to, update or alter its forward-looking statements, whether as a result of new information, future events or otherwise.

3. SunPower 2009 revenue of $1.5B ~1000 dealers and growing rapidly 550 MW 2010 production, >1 TWh cum 500+ MW power plants globally Diversified portfolio: roofs to power plants 5,000+ Employees; 100% solar Publicly listed NASDAQ: SPWRA, SPWRB 4+ GW power plant pipeline Power Plants Residential Commercial 3

4. Policy Tools Rate Design– energy prices determine economics of solar Incentives – direct rebates or incentives reduce upfront costs to customers, primarily used in res/commercial retail markets Financing – PACE, DOE Loan Guarantees, 3rd Party Ownership, other policies to reduce cost or improve access to financing Tax Policy – ITC, MITC, accelerated depreciation, Treasury Grants Net Energy Metering – NEMhelps with system sizing, long-term economics, large part of the CA value proposition for retail systems Renewable Portfolio/ Renewable Energy Standards – RPSorRESrequirements give the market targets and some security, may include tradeable Renewable Energy Credits (RECs) and/or solar carve-outs Feed-In Tariffs – FIT used extensively in Europe, these are “must-take, standard offer” terms for renewable generators, typically wholesale from 1-20 MW, price may be administratively set or by auction Interconnection (IC)/Jurisdiction– FERC, State PUCs, ISO/RTOs may have different rules or markets 4 Price Mandate Access

5. What do we (all?) want post CSI? Stable Policy Environment with multiple options for Solar PV Consumer Protection Safety, Protection from Fraud, Warranties Simplified or Standard Interconnection Procedures Financing Reasonable Barriers to Entry Equipment and Installer Standards Transparent cost comparisons 5

6. Why Barriers to Entry? Not all solar projects are created equal Long Term Value is the key to consumer satisfaction, investor confidence, public acceptance and policy support Reasonable barriers ensure that market participants and equipment are qualified and perform as expected Part of Consumer Protection as well Cost comparisons should use a transparent, standardized metric like Levelized Cost of Energy (LCOE) Low cost/low quality systems would not dominate the market because the value proposition would not hold up Diversity with standards is good for everybody 6

7. 7 SunPower: Most Energy Per Meter Squared Wafer Ingot Most powerful solar technology on the planet Direct Control: Ingot through Systems Solar Cell Solar Panel System Polysilicon

8. High Quality + High Efficiency = High Cost…. 8

10. Different applications require different solutions – space constraints, cost of energy, cost of finance, etc.

11. Ultimately consumers should be able to compare “apples to apples” and have high confidence in their information9

13. A. Kimber, “Long Term Performance of 60MW of Installed Systems in the US, Europe, and Asia”, Proceedings of the 22nd Annual Photovoltaic Solar Energy Conference, Sept. 200710