報告書番号

Y97013

タイトル（和文）

電源入札制度の価格設定と卸供給契約に関する考察

タイトル（英文）

SURVEY ON DESIGNING AUCTION PROCEDURES FOR NEW ELECTRIC GENERATING CAPACITY AND RISKS OF LONG-TERM POWER PURCHASE CONTRACTS WITH IPPS

概要 （図表や脚注は「報告書全文」に掲載しております）

本報告では，基本的な競争入札の理論を振り返った後，効率性の面でより優れているとされてきた統一価格方式による電源入札制度の可能性を検討した。統一価格方式による入札は，応札者に真の費用を提示させるインセンティブを与え，その結果，必ず効率的な電源調達が可能になると考えられてきた。しかし，米国の事例や最近の文献の調査から，統一価格方式には，応札者間の結託を助長する恐れがあることや，非価格要素も評価する場合に統一価格の設定が困難になること，そして，様々な取引関係を持つ企業には真の費用を提示することに抵抗感があること，と言った問題点があることが議論されており，その現実的な有効性は疑問視されている。また，本報告では電源入札後の長期受給契約に伴う電力会社のリスクについて整理し，その軽減策について予備的な考察を行った。米国の経験から，わが国でも，契約の短期化・柔軟化がリスク軽減策のひとつの選択肢となりうる。

概要 （英文）

THIS PAPER SUMMARIZES RECENT ARGUMENTS CONCERNING EFFICIENT PROCEDURES FOR AUCTION OF NEW ELECTRICITY GENERATION CAPACITY BY UTILITIES. THERE ARE TWO TYPES OF SEALED-BID AUCTION: A NON-UNIFORM PRICE (DISCRIMINATORY) AUCTION, AND A UNIFORM PRICE (COMPETITIVE) AUCTION. IT HAS BEEN ARGUED THAT IN THE UNIFORM PRICE AUCTION, BIDDERS ARE INDUCED TO REVEAL THEIR TRUE COST, LEADING TO EFFICIENT SELECTIONOF PROCUCERS. ELECTRIC UTILITIES IN JAPAN USE THE NON-UNIFORM PRICE AUCTION, WHILE IN CALIFORNIA, THE UNIFORM PRICE AUCTION HAD BEEN INTRODUCED FOR QF (QUALIFYING FACILITIES) AUCTION, BASED ON ITS THEORETICAL ADVANTAGE. HOWEVER, THE UNIFORM PRICE AUCTION MAY NOT BE EFFECTIVE IN ACTUAL AUCTION OF NEW GENERATING CAPACITY, BECAUSE: (1)IT FACILITATES COLLUSIVE BEHAVIOR AMONG BIDDERS, (2)IT IS DIFFICULT TO DETERMINE THE UNIFORM PRICE WHEN NON-PRICE FACTORS AS WELL AS PRICE FACTORS MUST BE EVALUATED, AND (3)BIDDERS ARE RELUCTANT TO REVEAL TRUE COSTS, FEARING THAT REVEALING SUCH INFORMATION WOULD BE A DISADVANTAGE IN SUBSEQUENT BUSINESS NEGOTIATIONS. IN ADDITION, THE LOSS IN EFFICIENCY ASSOCIATED WITH THE NON-UNIFORM PRICE AUCTION MAY NOT BE LARGE. IN A NON-UNIFORM PRICE AUCTION, IT CAN BE SHOWN THAT WHEN THERE IS A RISK OF FUTURE PRODUCTION, ELECTRIC UTILITIES SHOULD BEAR PART OF THE PRODUCERS RISK IN ORDER TO LOWER BID PRICES AND INDUCE FURTHER COST-REDUCING EFFORT. THE RISKS INVOLVED IN ENTERING LONG-TERM POWER PURCHASE CONTRACTS WITH INDEPENDENT POWER PRODUCERS (OR NON-UTILITY GENERATORS) ARE ALSO DISCUSSED. THESE RISKSARE CLASSIFIED INTO SEVERAL CATEGORIES. ELECTRIC UNILITIES IN THE USA TEND TO ENTER SHORT-TERM OR FLEXIBLE-TERM CONTRACTS WITH NON-UTILITY GENERATORS. CONSIDERING THE UNCERTAINTIES OF FUTURE DEMAND, FUEL PRICE, TECHNOLOGICAL PROGRESS, AND REGULATORY POLICY, ELECTRIC UTILITIES IN JAPAN SHOULD CONSIDER A COMBINATION OF SHORT- AND LONG-TERM CONTRACTS TO INTRODUCE GREATER FLEXIBILITY INTO THEIR RELATIONSHIP WITH IPPS.

報告者

キーワード