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United States

Securities and Exchange Commission

Washington, D.C. 20549

Form 10-Q

For the quarterly period ended March 31, 2011

OR

Commission File Number 001-34044

REAL GOODS SOLAR, INC.

(Exact name of registrant as specified in its charter)

833 W. SOUTH BOULDER ROAD

LOUISVILLE, COLORADO 80027-2452

(Address of principal executive offices)

(303) 222-8400

(Registrant’s telephone number, including area code)

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15 (d) of the Securities and Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports) and (2) has been subject to such filing requirements for the past 90 days.    YES  x    NO  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    YES  ¨    NO  ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of “large accelerated filer,” “accelerated filer,” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    YES  ¨    NO  x

Indicate the number of shares outstanding of each of the issuer’s classes of common stock, as of the latest practicable date:

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REAL GOODS SOLAR, INC.

FORM 10-Q

INDEX

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This report may contain forward-looking statements that involve risks and uncertainties. The words “anticipate,” “believe,” “plan,” “estimate,” “expect,” “strive,” “future,” “intend” and similar expressions as they relate to us are intended to identify such forward-looking statements. Our actual results could differ materially from the results anticipated in these forward-looking statements as a result of certain factors set forth under “Management’s Discussion and Analysis of Financial Condition and Results of Operations,” “Quantitative and Qualitative Disclosures about Market Risk”, “Risk Factors” and elsewhere in this report. Risks and uncertainties that could cause actual results to differ include, without limitation, general economic conditions, competition, adoption of solar energy technologies, loss of key personnel, pricing including pricing of conventional energy sources, the level of government subsidies and economic incentives for solar energy, changing energy technologies, our geographic concentration, brand reputation, consumer trends, acquisitions, new initiatives we undertake, security and information systems, legal liability for website content, merchandise and solar panel supply problems, product liabilities, failure of third parties to provide adequate service, our reliance on centralized customer service, overstocks and merchandise returns, our reliance on a centralized fulfillment center, increases in postage and shipping costs, E-commerce trends, future Internet related taxes, our majority shareholder’s control of us, our dependence on Gaiam, Inc. for certain services, fluctuations in quarterly operating results, customer interest in our products, the effect of government regulation and other risks and uncertainties included in our filings with the Securities and Exchange Commission. We caution you that no forward-looking statement is a guarantee of future performance, and you should not place undue reliance on these forward-looking statements which reflect our view only as of the date of this report. We undertake no obligation to update any forward-looking information.

PART I. FINANCIAL INFORMATION

Unaudited Interim Condensed Consolidated Financial Statements

We have prepared our unaudited interim condensed consolidated financial statements included herein pursuant to the rules and regulations of the United States Securities and Exchange Commission. Certain information and note disclosures normally included in annual financial statements prepared in accordance with accounting principles generally accepted in the United States have been condensed or omitted pursuant to these rules and regulations, although we believe that the disclosures made are adequate to make the information not misleading. In our opinion, the unaudited interim condensed financial statements contain all adjustments (consisting of only normal recurring adjustments) necessary to present fairly, in all material respects, our consolidated financial position as of March 31, 2011, the interim results of operations for the three months ended March 31, 2011 and 2010, and cash flows for the three months ended March 31, 2011 and 2010. These interim statements have not been audited. The balance sheet as of December 31, 2010 was derived from our audited consolidated financial statements included in our annual report on Form 10-K. The interim condensed consolidated financial statements contained herein should be read in conjunction with our audited financial statements, including the notes thereto, for the year ended December 31, 2010.

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REAL GOODS SOLAR, INC.

Condensed consolidated balance sheets

See accompanying notes to the interim condensed consolidated financial statements.

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REAL GOODS SOLAR, INC.

Condensed consolidated statements of operations

See accompanying notes to the interim condensed consolidated financial statements.

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REAL GOODS SOLAR, INC.

Condensed consolidated statements of cash flows

See accompanying notes to the interim condensed consolidated financial statements

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Notes to interim condensed consolidated financial statements

We are a leading residential and commercial solar energy integrator. We were incorporated in Colorado on January 29, 2008 under the name Real Goods Solar, Inc. (“Real Goods Solar”, “we”, “us”, or “our”). As of March 31, 2011, we were 54.6% owned by Gaiam, Inc. (“Gaiam”). Our initial public offering of common stock occurred on May 7, 2008.

We have prepared the accompanying unaudited interim condensed consolidated financial statements in accordance with accounting principles generally accepted in the United States, or GAAP, and they include our accounts and those of our subsidiaries. Intercompany transactions and balances have been eliminated.

The unaudited condensed consolidated financial position, results of operations and cash flows for the interim periods disclosed in this report are not necessarily indicative of future financial results.

No changes were made to our significant accounting policies during the three months ended March 31, 2011.

We have evaluated events subsequent to March 31, 2011 and concluded that no material event has occurred which would impact either the results reflected in this report or our results going forward.

Use of Estimates and Reclassifications

The preparation of financial statements in accordance with GAAP requires us to make estimates and assumptions that affect the amounts reported in the accompanying financial statements and disclosures. Although we base these estimates on our best knowledge of current events and actions that we may undertake in the future, actual results may be different from the estimates. We have made certain reclassifications to prior period amounts to conform to the current period presentations.

For large installations, we bill for contract performance progress each month. Billing requires completion of an application and certificate of payment form required by the contract, which is done after each month end. As a result, accounts receivable on our condensed consolidated balance sheet as of March 31, 2011 included $1.6 million of unbilled receivables, representing such contract performance progress.

During the first quarter of 2011, we issued 5,661 of our Class A common shares to our independent directors, in lieu of cash compensation, for services rendered during 2011. Following this transaction, Gaiam owned 54.6% of our stock.

During the first quarter of 2011, we granted 34,000 new stock options and cancelled 13,000 stock options under our 2008 Long-Term Incentive Plan. The new stock options vest at 2% per month for the 50 months beginning in the eleventh month after date of grant.

Total share-based compensation expense recognized was $0.1 million for each of the three months ended March 31, 2011 and 2010, and is shown in general and administrative expenses on our condensed consolidated statements of operations.

Basic net income per share excludes any dilutive effects of options. We compute basic net income per share using the weighted average number of common shares outstanding during the period. We compute diluted net income per share using the weighted average number of common shares and common stock equivalents outstanding during the period. We excluded common stock equivalents of 943,000 and 332,000 from the computation of diluted net income per share for the three months ended March 31, 2011 and 2010, respectively, because their effect was antidilutive.

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The following table sets forth the computation of basic and diluted net income per share:

During the three months ended March 31, 2011, we completed a project for our Chairman to design and install an upgrade to an existing solar system originally built in 1997 for Mr. Rysavy’s residence. The contract price or revenue recognized was $244 thousand, which is priced at a customary rate for work performed for employees. The contract price is included in our accounts receivable, net balance on our consolidated condensed balance sheet at March 31, 2011.

You should read the following discussion and analysis of our financial condition and results of operations in conjunction with the condensed consolidated financial statements and related notes included elsewhere in this document. This section is designed to provide information that will assist in understanding our condensed consolidated financial statements, changes in certain items in those statements from period to period, the primary factors that caused those changes and how certain accounting principles, policies and estimates affect the condensed consolidated financial statements.

Overview

We are a leading residential and commercial solar energy integrator. We offer turnkey solar energy services, including design, procurement, permitting, build-out, grid connection, financing referrals and warranty and customer satisfaction activities. We install residential and small commercial systems that are generally between 3 kW and 500 kW output, with the average residential installation being approximately 5 kW output. We also on occasion install larger commercial projects of up to 3MW output.

Our revenues primarily result from the installation of solar energy systems. We also derive a portion of our revenues from the retail sale of renewable energy products. Our expenses primarily consist of labor costs incurred in connection with solar installations, product costs for solar photovoltaic modules and other products sold, and related office and warehouse costs.

The first three months of 2011 were a record first quarter for us. The performance was particularly impressive given that this winter was one of the rainiest in California’s history. We grew revenues through marketing and sales initiatives, while at the same time controlled expenses by realizing significant cost savings through the integration of previously acquired businesses onto a single set of systems and a unified brand. As a result, we were able to maintain profitability during our seasonally slowest quarter. We were also able to increase our gross profit margin during the first quarter of 2011 due to improved selling and installation practices, as well as continued declines in PV module prices.

As we enter the second quarter of 2011, we anticipate continuing to build on our growth initiatives by expanding marketing and sales efforts to further leverage our solar installation capabilities. We continue to expect strong demand for both residential and commercial solar installations despite the overall economic weakness in the U.S.

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Results of Operations

The following table sets forth certain financial data as a percentage of revenue for the periods indicated:

Three Months Ended March 31, 2011 Compared to Three Months Ended March 31, 2010

Net revenue. Net revenue increased $2.4 million, or 16.1%, to $17.4 million during the first quarter of 2011 from $15.0 million during the first quarter of 2010. All the revenue growth was organic and was primarily driven by an increase in marketing and sales initiatives.

Gross profit. Gross profit increased $1.0 million, or 24.8%, to $5.0 million during the first quarter of 2011 from $4.0 million during the first quarter of 2010. As a percentage of net revenue, gross profit increased to 28.9% during the first quarter of 2011 from 26.9% during the first quarter of 2010. Approximately half of the increase in gross profit percentage was due to a shift in revenue mix towards higher margin residential installations, with most of the remainder due to lower product costs and improved selling and installation practices.

Selling and operating expenses. Selling and operating expenses increased $0.9 million, or 27.5%, to $4.3 million during the first quarter of 2011 from $3.4 million during the first quarter of 2010. As a percentage of net revenue, selling and operating expenses increased to 24.5% during the first quarter of 2011 from 22.4% during the first quarter of 2010. Approximately two-thirds of the percentage increase was the result of an investment in our commercial operations, with the remainder due to increased marketing and travel costs, partially offset by the leveraging of fixed costs.

General and administrative expenses. General and administrative expenses remained consistent at $0.7 million during the first quarters of 2011 and 2010. As of percentage of net revenue, general and administrative expenses decreased to 4.0% during the first quarter of 2011 from 4.3% during the first quarter of 2010, reflecting our leveraging of fixed costs.

Net income. As a result of the above factors, net income was $37 thousand during the first quarter of 2011 compared to $17 thousand during the first quarter of 2010. Net income per share was $0.00 per share during the first quarters of both 2011 and 2010.

Seasonality

Our quarterly net revenue and operating results for solar energy system installations are difficult to predict and have in the past and may in the future fluctuate from quarter to quarter as a result of changes in state, federal, or private utility company subsidies, as well as weather, economic trends and other factors. We have historically experienced seasonality in our solar installation business, with the first quarter representing our slowest installation quarter of the year. Additionally, the fourth quarter is often impacted by unfavorable weather in certain geographic regions. Much of the seasonality in our business in past years has been offset by the timing of government activities as well as the strong organic growth of our business.

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Liquidity and Capital Resources

Our capital needs arise from working capital required to fund our purchases of solar PV modules and inverters, capital related to acquisitions of new businesses, development of renewable energy products, replacements, expansions and improvements to our infrastructure, and future growth. These capital requirements depend on numerous factors, including business acquisitions, the ability to attract new solar energy system installation customers, market acceptance of our product offerings, the cost of ongoing upgrades to our product offerings, the level of expenditures for sales and marketing, the level of investment in support systems and facilities and other factors. The timing and amount of these capital requirements are variable and cannot accurately be predicted. We did not have any material commitments for capital expenditures as of March 31, 2011, and we do not presently have any plans for future material capital expenditures. During 2007 and 2008, we acquired four solar energy system installation businesses. We plan to continue to pursue business acquisition and other opportunities to expand our sales territories, technologies, and products and increase our sales and marketing programs as needed.

Cash Flows

The following table summarizes our primary sources (uses) of cash during the periods presented:

Operating activities. Our operating activities provided net cash of $2.3 million and used net cash of $0.3 million during the first quarters of 2011 and 2010, respectively. Our net cash provided by operating activities during the first quarter of 2011 was primarily attributable to decreased accounts receivable and inventory of $3.6 million and $0.6 million, respectively, and increased payable to Gaiam of $0.7 million, partially offset by decreased accounts payable and accrued liabilities of $1.9 million and $0.6 million, respectively, and noncash adjustments to net income of $0.3 million. Our net cash used in operating activities during the first quarter of 2010 was primarily attributable to decreased accounts payable, including our payable to Gaiam, of $0.9 million and increased accounts receivable of $1.1 million, partially offset by decreased deferred costs on uncompleted contracts and advertising of $0.9 million and increased inventory and other assets of $0.4 million and $0.3 million, respectively.

Investing activities. Our investing activities used net cash of $86 thousand and $129 thousand during the first quarters of 2011 and 2010, respectively. Our cash used in investing activities during the first quarters of 2011 and 2010 was used to acquire property and equipment.

We believe our available cash (which was approximately $13.4 million as of March 31, 2011) and cash expected to be generated from operations should be sufficient to fund our business for the foreseeable future. However, our projected cash needs may change as a result of possible acquisitions, unforeseen operational difficulties, or other factors. If required by our liquidity needs, we believe that we could obtain debt financing that would assist us in meeting any unanticipated cash requirements. In particular, our current assets (other than the cash balance referred to above) significantly exceed our current liabilities. In addition, to the extent debt financing was unavailable or if we elected not to proceed with debt financing, we may also consider equity financing to meet any unanticipated cash requirements.

In the normal course of our business, we investigate, evaluate and discuss acquisition, joint venture, noncontrolling investment, strategic relationship and other business combination opportunities in the solar energy markets. For any future investment, acquisition, or joint venture opportunities, we may consider using then-available liquidity, issuing equity securities, or incurring additional indebtedness.

Off-Balance Sheet Arrangements

We do not participate in transactions that generate relationships with unconsolidated entities or financial partnerships, such as special purpose entities or variable interest entities, which have been established for the purpose of facilitating off-balance sheet arrangements or other limited purposes.

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Contractual Obligations

We have commitments under operating leases and various service agreements with Gaiam, but do not have any outstanding commitments under long-term debt obligations or purchase obligations. The following table shows our commitments to make future payments under our operating leases:

To the extent we become entitled to utilize certain loss carryforwards relating to periods prior to our initial public offering, we will distribute to Gaiam the tax effect (estimated to be 34% for federal income tax purposes) of the amount of such tax loss carryforwards so utilized. Accordingly, we recognized a valuation allowance against all of our deferred tax assets as of the effective date of our tax sharing agreement with Gaiam, May 13, 2008. These net operating loss carryforwards expire beginning in 2018 if not utilized. Due to Gaiam’s step acquisitions of our company, we experienced “ownership changes” as defined in Section 382 of the Internal Revenue Code. Accordingly, our use of the net operating loss carryforwards is limited by annual limitations described in Sections 382 and 383 of the Internal Revenue Code. As of March 31, 2011, $5.0 million of these net operating loss carryforwards are available for current and future utilization, meaning that potential future payments to Gaiam, which would be made over a period of several years, could therefore aggregate to approximately $1.7 million based on current tax rates. Based upon our estimated utilization of some of these loss carryforwards on our tax returns, as of March 31, 2011 we recorded a payable to Gaiam of $0.5 million, which is subject to adjustment based on our final income tax returns.

Risk Factors

We wish to caution you that there are risks and uncertainties that could cause our actual results to be materially different from those indicated by forward looking statements that we make from time to time in filings with the Securities and Exchange Commission, news releases, reports, proxy statements, registration statements and other written communications as well as oral forward looking statements made from time to time by our representatives. These risks and uncertainties include, but are not limited to, those risks listed in our Annual Report on Form 10-K for the year ended December 31, 2010. Except for the historical information contained herein, the matters discussed in this analysis are forward-looking statements that involve risk and uncertainties, including, but not limited to, general economic and business conditions, competition, pricing, brand reputation, consumer trends, and other factors which are often beyond our control. We do not undertake any obligation to update forward-looking statements except as required by law.

We are exposed to market risks, which include changes in U.S. interest rates and foreign exchange rates. We do not engage in financial transactions for trading or speculative purposes.

We purchase a significant amount of our product inventory from vendors outside of the United States in transactions that are primarily U.S. dollar denominated transactions. Since the percentage of our international purchases denominated in currencies other than the U.S. dollar is small, any currency risks related to these transactions are immaterial to us. However, a decline in the relative value of the U.S. dollar to other foreign currencies could lead to increased purchasing costs. In order to mitigate this exposure, we make virtually all of our purchase commitments in U.S. dollars.

Evaluation of Disclosure Controls and Procedures

Our management, with the participation of our President and Chief Financial Officer, evaluated the effectiveness of our disclosure controls and procedures (as defined in Exchange Act Rule 13a-15(e)) at the end of the period covered by this report. Based on such evaluation, our President and Chief Financial Officer concluded that, at the end of such period, our disclosure controls and procedures were effective in alerting them, on a timely basis, to material information required to be disclosed in the reports that we file or furnish under the Securities Exchange Act of 1934.

Changes in Internal Control over Financial Reporting

No changes in our internal control over financial reporting occurred during the quarter ended March 31, 2011 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

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PART II. OTHER INFORMATION

From time to time, we are involved in legal proceedings that we consider to be in the normal course of business. We do not believe that any of these proceedings will have a material adverse effect on our business.

No material changes.

None.

None.

None.

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Signatures

In accordance with the requirements of the Securities and Exchange Act, the registrant caused this report to be signed on its behalf, by the undersigned, thereunto duly authorized.

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