兩位分析師認為，如果要擁有成本競爭力，太陽能的單位發電成本必須減少三分之二，而只有大規模擴張才可能實現這樣的目標：

 

我們預計，一塊安裝后的太陽能板將必須從今天的每瓦特4.4美元減少到每瓦特1.4美元，在成本方面才有能力與新建成的天然氣發電廠發電競爭，前提是天然氣發電廠必須為碳排放支付每公噸50美元的費用。而為了適應能源儲存的需要，這種太陽能發電的成本還必須減少到每瓦特1.1美元。但要達到這個價位就需要大規模經濟擴張。

 

為完全滿足2025年的用電需求，需要發電大約1000萬兆瓦，相當于太陽能板大概要覆蓋美國佛蒙特州和新罕布什爾州全境。

 

但實現電網平價的成本將是天文數字，必須為此“支付數萬億美元”。

 

 

兩位分析師提到了德國的經歷：

 

大部分資金可能都會浪費。比如德國已經補貼了大約500億美元，但太陽能只貢獻了發電量的6%。邊際稅收在大學的研究實驗室會找到更好的歸宿。在那里，基礎技術的突破更有可能大幅提高效率，相應地降低價格。

 

這并不等于說太陽能發電在全球沒有存在的空間：

 

在缺少基礎設施的印度鄉村或者非洲部分地區，太陽能可能實際上是提供基礎發電的最廉價方式。即使在基礎設施發達的特定市場，天氣最熱的時候，事實可能證明，少量的太陽能發電是提供電力的有價值方式。

 

所以，他們的觀點就是，對目前缺少發電基礎設施的地區，太陽能可能是可行的，但發達世界還是忘了它吧。

 

 

Finding Economies of Scale in Solar
 

Posted by Catherine Wood on Oct 8, 2012 in AllianceBernstein, Equities/Stocks | 0 comments

 

By Catherine Wood and Brett Winton
 

Advocates of solar energy have argued for years that the industry only needs subsidies to gain the economies of scale that would make it cost competitive. We think that day may never arrive.
 

Solar power is expensive to produce because the equipment is expensive and only works a fraction of the time—30% of the time in the optimal spots for solar energy, such as the Las Vegas desert. Nuclear or coal power plants, by contrast, can run almost round the clock, day in and day out.
 

We estimate that the cost of an installed solar power panel would have to fall from about $4.40 per watt today to $1.40 per watt to become cost competitive with a newly built natural gas–fired plant, assuming the gas plant had to pay $50 per metric ton for carbon emissions. It would have to fall to about $1.10 per watt to accommodate the cost of energy storage. But to get to that price, massive economies of scale would be required.
 

In the power business, there’s a rule of thumb: each time you double the cumulative installed base of power-generating infrastructure, the cost of a new installation should fall by 20%. Since 1976, the cost of solar power has declined somewhat less, by 18% on average, for every doubling of installed capacity. Over the past ten years, costs have fallen 13% for every doubling.
 

But let’s say the cost declines return to the 18% rate. How much solar power would have to be installed before incremental solar panels would be truly cost competitive? 9.6 million megawatts, or more than 100 times the capacity in place today, as the display below shows. With an area of 20,000 square miles, these panels together would be large enough to cover Vermont and New Hampshire, and produce annual quantities of electricity sufficient to exceed demand for the entire world through 2025.

 

So when is solar going to become cost competitive without subsidies? In three to five years? Try never. But if it did, society would have to pay out trillions of dollars to get there.
 

That doesn’t mean solar energy is a complete dead end. Solar power may indeed be the cheapest way to provide base electric power in rural India, or in parts of Africa devoid of infrastructure. Even in select markets with developed infrastructure, a small amount of solar power may prove valuable to provide electricity during the hottest parts of the day.
 

But should governments provide massive subsidies to support solar energy in places where electric power can be generated at a much lower cost?
 

I think not. Much of the money is likely to be wasted. Germany, for example, has subsidized the solar industry to the tune of $50 billion, yet it only gets 6% of its electricity from solar power. The marginal tax dollar would find a better home in the research labs of universities, where fundamental technological breakthroughs are more likely to yield a big increase in efficiency and corresponding decline in price.
 

The views expressed herein do not constitute research, investment advice or trade recommendations and do not necessarily represent the views of all AllianceBernstein portfolio-management teams.
 

Catherine Wood is Chief Investment Officer—Thematic Portfolios, and Brett Winton is a research analyst, both at AllianceBernstein.