
LETTERTO STOCKHOLDERS OF HELIOGEN,INC. Dear Heliogen Stockholders: OnMay28,2025,Zeo Energy Corp.(which we refer to as“Zeo Energy”),HyperionMerger Corp.,a Delaware corporation and a direct,wholly-owned subsidiaryofZeo Energy(which we refer to as“Merger SubI”),Hyperion Acquisition LLC,aDelawarelimited liability company and a direct,wholly-owned subsidiary of ZeoEnergy (which we refer to as “Merger SubII” and, together with Merger Sub I, the“MergerSubs”)and Heliogen,Inc.(which we refer to as“Heliogen”)entered intoanAgreement and Plan of Merger and Reorganization(which,as it may be amended fromtimeto time,we refer to as the“Merger Agreement”)providing for the acquisitionofHeliogen by Zeo Energy in an all stock transaction.Subject to the terms andsatisfaction(or,if applicable,waiver)of the conditions of the Merger Agreement,theMerger Agreement provides that Merger SubIwill be merged with and intoHeliogen (which merger we refer to as the “First Merger”), with Heliogen continuingasthe surviving company and as a wholly owned subsidiary of Zeo Energy(which wereferto as the“First Surviving Corporation”).We refer to the time of the FirstMergeras the“Effective Time.” Immediately following the Effective Time,Heliogen,asthe First Surviving Corporation,will be merged with and into Merger SubII(whichwe refer to as the“Second Merger” and,together with the First Merger,the“Mergers”),with Merger SubIIsurviving the Second Merger as a wholly ownedsubsidiary of Zeo Energy (which we refer to as the “Surviving Company”). Subjectto the terms and conditions of the Merger Agreement,at the EffectiveTime, each issued and outstanding share of common stock, par value $0.0001 per share,ofHeliogen(“Heliogen Common Stock”)(other than shares of Heliogen Common Stockheldby Zeo Energy,Heliogen or their respective subsidiaries immediately prior totheEffective Time)will be cancelled and automatically converted into the right toreceive (i)a number of shares of Class A common stock, par value $0.0001 per share,ofZeo Energy(“Zeo Energy Class A Common Stock”)equal to the Exchange Ratio(asdefinedbelow)(the“Share Merger Consideration”),and(ii)if applicable,cash inlieuof fractional interest in such shares,rounded to the nearest cent,withoutinterest (together with the Share Merger Consideration, the “Merger Consideration”),subjectto any required tax withholding.The Zeo Energy ClassACommon Stock istradedon the Nasdaq Capital Market under the symbol“ZEO,”and such Zeo EnergyClassA Common Stock comprising the Merger Consideration is being registered in theregistrationstatement,of which the accompanying proxy statement/prospectus forms apart. Asprovided in the Merger Agreement,the“Exchange Ratio”is the quotientobtainedby dividing(i)thequotient of(A)theTotal Merger Consideration(asdefined below) divided by (B)the fully diluted share count of Heliogen Common StockoutstandingasofimmediatelypriortotheEffectiveTime(includingsharesunderlyingor issuable upon the conversion of outstanding shares of Heliogen’spreferredstock(if any)),in-the-money options,Heliogen’s restricted stock units,andthe Heliogen commercial warrants but excluding shares underlying special purposeacquisitioncompany warrants(the“Heliogen Fully-Diluted Shares”)by(ii)$1.5859(beingdefined as the Parent Stock Price).As provided in the Merger Agreement,the“Total Merger Consideration” is $10.0million, less (x)50% of any amount by whichtheHeliogen Net Cash(as defined below)at the closing of the First Merger(the“Closing”)is less than$13.0million(the“Net Cash Collar Floor”),or plus(y)50%of any amount by which the Heliogen Net Cash at the Closing is more than$16.0million(the“Net Cash Collar Ceiling”);and“Heliogen Net Cash”is anamountequal to the cash and cash equivalents and other current assets of Heliogenandits subsidiaries as of the Closing,less certain specified liabilities ofHeliogenand its subsidiaries as of the Closing,including unpaid transactionexpenses.Zeo Energy’s obligation to consummate the Closing is conditioned on theHeliogen Net Cash at Closing being equal to or greater than $10million, unless suchcondition is waived by Zeo Energy. Thenumber of shares of Zeo Energy ClassACommon Stock comprising the MergerConsideration,which results from the calculation of the Exchange Ratio,depends onthe number of Heliogen Fully Diluted Shares and the amount of Heliogen Net Cash as ofClosing,as described above,which will not be finally determined until threebusinessdays prior to the Closing.Solely for purposes of illustration,based onHeliogenFully-Diluted Shares of 6,605,298 as of June 24,2025,and assuming solelyfor illustration purposes that the amount of Heliogen Net Cash at Closing is not lessthan$13.0 million and not greater than$16.0 million,then the Exchange Ratio wouldbeapproximately 0.9546.Based on this illustrative Exchange Ratio and the number ofshares of Zeo Energy Class A Common Stock outstanding as of June24, 2025, the formerholders of Heliogen Common Stock would own Table of Contents ap