????在20世紀60年代的經典電影《畢業生》中，對于年輕的達斯汀·霍夫曼的未來，一位男子吼出這樣一個建議：“我只想跟你說一個詞，就一個詞。塑料業。”對現在的可再生能源領域而言，其未來也可以總結為一個詞：儲存。

????可再生能源正在迅速發展。即使是我在石油和天然氣行業的朋友也承認，未來的能源結構會與現在大不相同，可再生能源將占據大得多的份額。真正的問題是，這個未來距離現在究竟有多近（或多遠）。

????從現有的技術來推斷，化石能源產業還將繁榮相當長的時間。在2015年《世界能源展望》中，埃克森石油公司預計，太陽能產業的規模將增長20倍，風能將增長5倍——不過到2040年，所有可再生能源在全球能源供應的占比依舊不到10%。在預測2035年的能源前景時，英國石油公司也給出了類似的結論。

????原因在于，人們希望按下開關就看到燈亮起來。而可再生能源（除了輝煌時代已過的水電）卻無法實現這一點，它們總是需要另一種備用能源，即化石能源或核能。以德國為例，經濟技術部長菲利普·勒斯勒爾表示，盡管他們大力投資了可再生能源，但“對常規發電站的需求在未來幾乎不會減少”。“當無風或是多云的時候，常規發電站需要頂替上來，以滿足絕大部分能耗，保證能源供應的穩定……在目前來看，只有靈活的常規發電站能做到這一點。”

????可再生能源想要發展到非常大的規模，按照咨詢專家的話來說，需要做一件能“改變全局的事”。如果能夠以經濟可行的成本儲存太陽能和風能，并按需供應，就能從根本上改變全球的能源格局。

????這一理念既不新穎，也不是異想天開。利用抽水蓄能系統來進行水力發電已有幾十年歷史，現在的手機電池也是一種儲能的方式。這項技術只是還沒有應用到風能或太陽能上。這個局面終將發生改變。著名能源咨詢公司IHS預計，能源儲存量將會從2013年的3億多瓦發展到2017年的60億瓦，再到2022年的400億瓦。麥肯錫公司在2013年估計，到2025年時，全球能源儲存帶來的經濟影響至少會達到每年900億美元，如果它能迅速應用于汽車的話，其經濟影響可能更大（最高達到6350億美元）。相對于全球能源市場的6萬億來說，這只是滄海一粟，但它在不斷壯大。

????實際上，就如我們過去十年中在頁巖氣和太陽能領域看到的一樣，數十年的努力加上數十項創新成果，讓技術突破了臨界點，其使用率隨之飛速提高。我認為儲存技術也是一樣。我們已經見證過許多先例。

????尤其要提到的是，目前已經有大量試驗正在進行，從支持153兆瓦風電場的系統，到控制曼哈頓市中心一座摩天大樓溫度和照明的系統，再到為阿拉斯加獨立設施提供后備支持的系統。不是所有這些系統都能發揮作用，或是效果很好，或是足夠便宜到大規模應用。不過任何創新都是這樣，重要的是人們開始嘗試把各種想法付諸現實。其中總有一部分能夠成功。

????同樣值得指出的是，現有的儲存技術也變得更便宜了。2007年，大容量鋰離子電池的儲存價格約為每千瓦時900美元，現在已經降到了380美元，到2020年可能會降至200美元。還有其他類型的電池可能會超越，或者至少完善鋰離子電池，例如液態金屬電池、鋰空氣電池、鋰硫電池、鈉離子電池、納米超級電容器，以及能源緩存技術。

????最后，關于可再生能源改善存儲技術這一點，公共事業公司并不反對，實際上，他們正在進行相關投資。這很重要，因為我們需要電網，而能源儲存實際上可以強化電網的能力。目前，公共事業公司為了滿足偶爾的用電高峰，必須設計出額外負荷，而美國人通常使用的電量還不到電網全部承載力的30%。如果這些公司能在用戶需求低的時候把能源存儲起來，到高峰期再釋放這些能源，就能節省大量資金，同時還能消除頻率波動，提供電壓支持。再次引用咨詢專家常說的話，這叫雙贏。

????我不是一個盲目樂觀的人。我知道想要讓能源儲存成為主流，還有大量障礙需要克服。正如落基山研究所冷靜的環保學家最近所言，目前沒有哪種能源儲存方式“創造的收益能接近所需的成本”。麥肯錫全球研究所也指出，許多重要問題有待解決。

????不過整體情況就是這樣。全球有許多聰明人在研究能源儲存。越來越多的人開始為他們研究提供資金支持。成本正在降低。科技正在飛速發展。人們對這項技術有很大需求。用一個詞來概括所有這些趨勢指向的結果，那就是：進步。（財富中文網）

????斯科特·尼奎斯特是麥肯錫石油和天然氣業務、以及可持續發展與資源生產力網絡的全球領導人。

????譯者：嚴匡正

????審校：任文科

????In the 1960s classic film, The Graduate, a man barks advice to a young Dustin Hoffmann about his future: “I just want to say one word to you. Just one word. Plastics.” For the renewable energy industry these days, its future can also be summed up in one word: storage.

????Renewables are growing. Even many of my friends in the oil and gas industry concede that the energy mix of the future is going to look a lot different from the one we have now—and renewables will be a much bigger part of the picture. The real question is how close (or distant) that future is.

????Based on current technologies, the conclusion of the fossil fuel industry is—pretty darn far. In its 2015 Outlook on Energy, for example, Exxon XOM 0.59% projects that solar will grow by a factor of 20 and wind by five—but that by 2040 all renewables will still make up less than 10 percent of the global power supply. In its projections to 2035, BP BP 0.80% ends up in the same neighborhood.

????The reason is that people really do want to be able to flip a switch and see the lights come on. Renewables (other than hydro, which has had its day) cannot deliver that; there always needs to be another source of backup power, which means fossil fuels or nuclear. Consider Germany. Even though it is investing heavily in renewables, it “will continue to need almost as many conventional power stations as before,” noted technology minister, Philipp Rosler. “When there is no wind, or it is cloudy, conventional power stations need to jump in and cover the bulk of energy consumption so that the electricity supply can be maintained securely. …At present, only flexible conventional power stations can do this.”

????What renewables need to scale up to the very big time, then, is a game-changer (to use some consultant-speak). If solar or wind power could be economically stored, then released on command, that could fundamentally change the world’s power dynamics.

????This idea is neither new nor fantastic. Hydro has used pumped storage systems for decades; your cellphone’s battery is a form of storage. But the technology basically doesn’t exist for wind or solar. That could be changing. IHS, the respected energy consultancy, projects that energy storage will grow from a one-third of a gigawatt in 2013 to 6 GW by 2017 and more than 40 GW by 2022. In 2013, McKinsey estimated that the economic impact of energy storage would be at least $90 billion a year by 2025, and possibly much more (up to $635 billion) depending on how fast it is applied to cars. This is a drop in the bucket that is the $6 trillion global energy market—but it is a drop that is getting bigger.

????In fact, as we have seen with both shale and solar over the last decade, decades of work and dozens of innovations can come together and create a tipping point where use dramatically increases. I think that could happen with storage. We are seeing many of the same dynamics.

????Specifically, there are tons of experiments going on, ranging from a system that supports a 153-megawatt wind farm in Texas to one in midtown Manhattan that keeps a skyscraper cool, warm, and lit to one that provides backup support for isolated utilities in Alaska. Not all of these will work, or work well enough, cheaply enough to scale up. But that is true of any innovation; what matters is that lots of ideas are being tried. Some of them will succeed.

????It’s worth noting, too, that the storage technologies that do exist are getting cheaper. In 2007, the cost of large-format lithium-ion storage was about $900 per kilowatt-hour; that is down to about $380, and could drop below $200 by 2020. There are other promising battery technologies that could leapfrog or at least complement li-ion, such as liquid metal, lithium-air, lithium-sulfur, sodium-ion, nano-based supercapacitors, and energy cache technology.

????Finally, this is one area concerning renewables that the utilities are not fighting; in fact, they are investing. That matters, because we need the grid, and storage could actually strengthen it. Right now, utilities have to build extra capacity just to meet occasional peaks; the US typically uses less than 30 percent of capacity. If utilities could store power during periods of low demand, then release it during peaks, that would save a ton of money on capital costs, while also smoothing out frequency variations and providing voltage support. To venture into consultant speak again, that’s a win-win.

????I am not a green-tinted Pollyanna. I know that there are lots of hurdles before storage becomes mainstream. As the hard-headed environmentalists at the Rocky Mountain Institute put it recently, there is no energy-storage business model at the moment that “offers anything close to a cash-positive scenario.” The McKinsey Global Institute cautions that there are many big issues that need to be addressed.

????But the big picture is this. There are many smart people, all over the world, working on energy storage. Investment in their research is growing. Costs are falling. Technologies are proliferating. And people want it. There is one word that sums up the likely consequence of those trends: progress.

????Scott Nyquist is a global leader in McKinsey’s oil & gas practice and also its Sustainability & Resource Productivity Network. He writes a column for LinkedIn on energy and environmental issues.