VeraSun Energy and US BioEnergy Announce Merger Agreement

Combination Expected to Reach Ethanol Production Capacity of More

than 1.6 Billion Gallons by End of 2008BROOKINGS, S.D. & ST. PAUL, Minn.--(Business Wire)--VeraSun Energy Corp. (NYSE:VSE) and US BioEnergy Corp.

(NASDAQ:USBE) today announced they have entered into a definitivemerger agreement, which has been unanimously approved by the board ofdirectors of each company. The merger is expected to close during thefirst quarter of 2008, pending shareholder approval, anti-trustregulatory clearance and the completion of other customary conditions. Under the merger agreement, 0.81 share of VeraSun common stockwill be issued for each outstanding share of US BioEnergy commonstock, representing a premium of approximately 11 percent based onNovember 23, 2007, closing prices. The existing VeraSun shares willremain outstanding and will represent approximately 60 percent of theshares outstanding after the merger. VeraSun Chairman, CEO and President Donald L. Endres will remainCEO of the combined company, and US BioEnergy President and CEO GordonOmmen will serve as chairman following the closing of the merger.VeraSun Senior Vice President and Chief Financial Officer Danny C.Herron will become president of the combined company. The combinedentity will retain the VeraSun name and trade under VeraSun's existingNYSE ticker symbol, VSE. "This merger is an opportunity for two leading companies in therenewable fuels industry to capitalize on synergies and provide valuefor shareholders," said Endres. "It also underscores the commitment ofeach company to execute on its growth strategy to become alarge-scale, low-cost ethanol producer. We are pleased with theopportunity to build a very unique industry platform." The merger is expected to create a stronger business platform byimproving access to capital and allowing the combined company toleverage technology and operating experience across its entire plantfleet. The merger is also expected to be accretive to VeraSun'searnings in the first full fiscal year of combined operations, and thecombined company is projected to have a market capitalization ofapproximately $1.5 billion. Upon completion of the merger, the combined company will have nineethanol production facilities in operation and seven additionalfacilities under construction. By the end of 2008, the company isexpected to have a total production capacity of more than 1.6 billiongallons per year (BGY) and 16 facilities constructed by Fagen, Inc.and utilizing ICM process technology. Through the merger, theemployees of both companies will be integrated into a combined workforce. "We're excited about the merger because it brings together twotalented and high-performing teams whose passion is to reduce ournation's dependence on foreign oil through the production of cleanrenewable biofuels," said Ommen. "By harnessing the collectivestrength of both organizations, we expect to reach 1.6 billion gallonsof ethanol production capacity by the end of 2008, making us a globalleader in ethanol production." In connection with the merger, holders of a significant percentageof the outstanding shares of each company have agreed to vote in favorof the transaction. Morgan Stanley & Co. Incorporated is serving as financial adviser,and Cravath, Swaine & Moore LLP is acting as legal counsel for VeraSunin the transaction. UBS Securities LLC is serving as financialadviser, and Skadden, Arps, Slate, Meagher & Flom LLP is acting aslegal counsel for US BioEnergy in the transaction. Production Profile-0-*T

Size

-----------Current Operating Facilities Owner (MMGY) Startup--------------------------------------------------------------------------------------------------------------------------------------------Aurora, South Dakota VSE 120 2003--------------------------------------------------------------------------------------------------------------------------------------------Platte Valley, Nebraska USBE 100 2004--------------------------------------------------------------------------------------------------------------------------------------------Fort Dodge, Iowa VSE 110 2005--------------------------------------------------------------------------------------------------------------------------------------------Woodbury, Michigan USBE 50 2006--------------------------------------------------------------------------------------------------------------------------------------------Albert City, Iowa USBE 110 2006--------------------------------------------------------------------------------------------------------------------------------------------Ord, Nebraska USBE 50 2007--------------------------------------------------------------------------------------------------------------------------------------------Charles City, Iowa VSE 110 2007--------------------------------------------------------------------------------------------------------------------------------------------Linden, Indiana VSE 110 2007--------------------------------------------------------------------------------------------------------------------------------------------Albion, Nebraska VSE 110 2007-------------------------------------------------------------------------------------------------------------------------------------------- Capacity in Operation 870---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Size -----------Planned Operating Facilities Owner (MMGY) Projected Startup--------------------------------------------------------------------------------------------------------------------------------------------Bloomingburg, Ohio VSE 110 Q1 2008--------------------------------------------------------------------------------------------------------------------------------------------Marion, South Dakota USBE 110 Q1 2008--------------------------------------------------------------------------------------------------------------------------------------------Welcome, Minnesota VSE 110 Q2 2008--------------------------------------------------------------------------------------------------------------------------------------------Hartley, Iowa VSE 110 Q2 2008--------------------------------------------------------------------------------------------------------------------------------------------Dyersville, Iowa USBE 110 Q2 2008--------------------------------------------------------------------------------------------------------------------------------------------Hankinson, North Dakota USBE 110 Q2 2008--------------------------------------------------------------------------------------------------------------------------------------------Janesville, Minnesota USBE 110 Q3 2008--------------------------------------------------------------------------------------------------------------------------------------------Reynolds, Indiana VSE 110 2009(a)-------------------------------------------------------------------------------------------------------------------------------------------- Capacity Under Construction or Development 880-------------------------------------------------------------------------------------------------------------------------------------------- Total Operating Capacity-------------------------------------------------------------------------------- Upon Completion of all Facilities 1.75BGY--------------------------------------------------------------------------------------------------------------------------------------------*T (a) Assuming construction resumes in 2008, which will depend onmarket conditions. Conference Call Information VeraSun and US BioEnergy will host a live conference call andwebcast at 9 a.m. EST/8 a.m. CST, Thursday, November 29, 2007.VeraSun's participants will include Chairman, CEO and President DonaldL. Endres, and Senior Vice President and Chief Financial Officer DannyC. Herron. US BioEnergy participants will include President and CEOGordon Ommen and Senior Vice President and Chief Financial OfficerRich Atkinson. To listen to the conference call by phone, domestic callers maydial (800) 573-4840 and enter access code 58619128. Internationalcallers may dial (617) 224-4326 and enter access code 58619128. A livewebcast can be accessed on VeraSun's Web site athttp://www.verasun.com or US BioEnergy's Web site athttp://www.usbioenergy.net. A replay will be available within 24 hoursafter the conclusion of the call. To access the replay, dial (888)286-8010 and enter access code 53713120. International callers mayaccess the replay by dialing (617) 801-6888 and entering access code53713120. About VeraSun Energy Corporation VeraSun Energy Corporation (NYSE:VSE), headquartered in Brookings,SD, is a leading producer of renewable fuel. Founded in 2001, thecompany has 560 million gallons per year (MMGY) of production capacitythrough five operating ethanol production facilities in Aurora, SD,Fort Dodge, IA, Charles City, IA, Linden, IN and Albion, NE. Fourfacilities are currently either under construction or development inHartley, IA, Welcome, MN, Reynolds, IN, and Bloomingburg, OH. Uponcompletion of the new facilities, VeraSun will have an annualproduction capacity of approximately one billion gallons. The companyalso has plans to extract oil from dried distillers grains, aco-product of the ethanol process, for use in biodiesel production. The company markets E85, a blend of 85 percent ethanol and 15percent gasoline for use in Flexible Fuel Vehicles (FFVs), directly tofuel retailers under the brand VE85(TM). VeraSun now has approximately150 VE85(TM) retail locations under contract in over a dozen statesand Washington, D.C. For more information, please visit VeraSun'swebsites at www.verasun.com or www.VE85.com. About US BioEnergy Corporation US BioEnergy Corporation (NASDAQ:USBE), based in St. Paul, Minn.,is a producer and marketer of ethanol and distillers grains. Foundedin 2004, the company currently owns and operates four ethanol plantsin Albert City, IA, Ord, NE, Platte Valley, NE, and Woodbury, MI. Fouradditional ethanol plants are currently under construction in Marion;SD, Hankinson, ND, Dyersville, IA, and Janesville, MN. Upon completionof these initiatives, the company will own and operate eight plantswith combined expected ethanol production capacity of 750 milliongallons. Notes In connection with the proposed transaction between VeraSun and USBioEnergy, VeraSun will file a registration statement on Form S-4 withthe SEC. Such registration statement will include a joint proxystatement of VeraSun and US BioEnergy that also constitutes aprospectus of VeraSun, and will be sent to the shareholders of VeraSunand US BioEnergy. Shareholders are urged to read the joint proxystatement/prospectus and any other relevant documents when they becomeavailable, because they will contain important information aboutVeraSun, US BioEnergy and the proposed transaction. The joint proxystatement/prospectus and other documents relating to the proposedtransaction (when they are available) can be obtained free of chargefrom the SEC's website at www.sec.gov. These documents (when they areavailable) can also be obtained free of charge from VeraSun uponwritten request to VeraSun Energy Corporation, Attention: InvestorRelations, 100 22nd Avenue, Brookings, South Dakota 57006, or bycalling 605-696-7236, or from US BioEnergy, upon written request to USBioEnergy Corporation, Attention: Investor Relations, 5500 CenexDrive, Inver Grove Heights, Minnesota 55077, or by calling651-554-5491. This communication is not a solicitation of a proxy from anysecurity holder of VeraSun or US BioEnergy. However, VeraSun, USBioEnergy and certain of their respective directors and executiveofficers may be deemed to be participants in the solicitation ofproxies from shareholders in connection with the proposed transactionunder the rules of the SEC. Information about the directors andexecutive officers of VeraSun may be found in its 2006 Annual Reporton Form 10-K filed with the SEC on March 29, 2007, definitive proxystatement relating to its 2007 Annual Meeting of Shareholders filedwith the SEC on April 12, 2007 and current reports on Form 8-K filedwith the SEC on July 3, 2007, August 31, 2007 and September 20, 2007.Information about the directors and executive officers of US BioEnergymay be found in its 2006 Annual Report on Form 10-K filed with the SECon March 30, 2007, definitive proxy statement relating to its 2007Annual Meeting of Shareholders filed with the SEC on April 27, 2007and current reports on Form 8-K filed with the SEC on August 13, 2007,October 3, 2007 (as amended) and November 6, 2007. These documents canbe obtained free of charge from the sources indicated above.Additional information regarding the interests of these participantswill also be included in the proxy statement/prospectus regarding theproposed transaction when it becomes available. This document includes or incorporates by reference financialestimates and other forward-looking statements within the meaning ofthe Private Securities Litigation Reform Act of 1995. These estimatesand statements are subject to risks and uncertainties, and actualresults might differ materially from these estimates and statements.Such estimates and statements include, but are not limited to,statements about the benefits of the merger, including futurefinancial and operating results, the combined company's plans,objectives, expectations and intentions, and other statements that arenot historical facts. Such statements are based upon the currentbeliefs and expectations of the management of VeraSun and are subjectto significant risks and uncertainties outside of its control. The following factors, among others, could cause actual results todiffer from those described in the forward-looking statements in thisdocument: the ability to obtain governmental approvals of the mergeron the proposed terms and schedule; the failure of VeraSunshareholders to approve the issuance of VeraSun common shares or thefailure of US BioEnergy shareholders to approve the merger; the riskthat the businesses of VeraSun and US BioEnergy will not be integratedsuccessfully or as quickly as expected; the risk that the cost savingsand any other synergies from the merger may not be fully realized ormay take longer to realize than expected; disruption from the mergermaking it more difficult to maintain relationships with customers,employees or suppliers; and competition and its effect on pricing,spending, third-party relationships and revenues. Additional factorsthat may affect future results are contained in VeraSun's and USBioEnergy's filings with the Securities and Exchange Commission("SEC"), which are available at the SEC's Web site(http://www.sec.gov). VeraSun is not under any obligation, andexpressly disclaims any obligation, to update, alter or otherwiserevise any forward-looking statement, whether written or oral, thatmay be made from time to time, whether as a result of new information,future events or otherwise.VeraSun Contacts:Investors:Patty Dickerson, 605-696-7236pdickerson@verasun.comorMedia:Mike Lockrem, 605-696-7527mlockrem@verasun.comorUS BioEnergy Contacts:Investors:Rich Atkinson, 651-554-5491investor@usbioenergy.netorMedia:JD Bergquist, 651-554-5490media@usbioenergy.netCopyright Business Wire 2007