據普氏能源資訊7月18日報道，自夏季開始以來，美國西海岸的柴油差價已大幅下降，因為庫存和煉油廠利用率已從春季維護季節恢復。

周三，洛杉磯的加州級柴油在紐約商品交易所(Nymex)8月超低硫柴油(ULSD)加2美分/加侖的價格進行了評估，這是自6月20日期貨價格持平以來的最低價格。該評級是在前一個月期貨加上5月7日38美分/加侖的水平上評估的，這是自2011年11月以來的最高水平。

根據普氏分析的數據顯示，西海岸煉油廠維護在截至3月29日的一周達到頂峰，當時蒸餾產能約為342萬桶/日，而本周的預計產能僅為145萬桶/日。

根據能源信息管理局(Energy Information Administration )周三公布的數據顯示，煉油廠的利用率在7月12日結束的一周達到95.3%,從三月底到五月底，煉廠產能利用率停滯在90％以下，時間當差已經飆升。

隨著煉廠重新上線，碳水化合物-柴油的供應增加。據加州能源委員會的最新數據顯示，截至7月5日的這一周，中質產品的產品產量提高了22.7%，達到了145.7萬桶。

圣弗朗西斯科普通碳水化合物柴油周三在8月份的商品期貨加6美分/加侖的價格上進行了評估，這是自6月27日以來的最低價格。

供應增加并不僅僅是加利福尼亞州。根據EIA數據顯示，美國西海岸超低硫柴油庫存較上周上漲100萬桶至1248.1萬桶。 從4月底到5月底，庫存仍然低于1200萬桶。

在波特蘭柴油成本是八月期貨加6.50美分/加侖，自6月21日的最低水平。

郝芬 譯自 Platts

原文如下：

US West Coast diesel differentials decline after spring peak

US West Coast diesel differentials have fallen dramatically since summer began as stocks and refinery utilization percentages have recovered from the spring maintenance season.

California-grade diesel in Los Angeles was assessed Wednesday at NYMEX August ULSD plus 2 cents/gal, its lowest price since it was flat to futures on June 20. The grade was assessed at front-month futures plus 38 cents/gal May 7, its highest level since November 2011.

West Coast refinery maintenance peaked in the week ended March 29 when about 3.42 million b/d of distillation capacity was under work, compared to just 1.45 million b/d of expected capacity for this week, according to Platts Analytics.

Refinery utilization finished the week ended July 12 at 95.3%, according to Energy Information Administration data published Wednesday. From late March to late May, refinery utilization stagnated below 90%, the time when the differentials had spiked.

As refineries came back online, CARB-diesel supply increased. Production for the week ended July 5 rose 22.7% on the week to 1.457 million barrels, according to the latest California Energy Commission data.

San Francisco CARB-diesel was assessed Wednesday at August futures plus 6 cents/gal, the lowest price since June 27.

The supply increase has not been isolated to just California. Total West Coast ULSD stocks rose 1 million barrels last week to 12.481 million barrels, EIA data showed. From the end of April to the end of May, stocks remained under 12 million barrels.

Diesel costs in Portland were August futures plus 6.50 cents/gal, the lowest level since June 21.