LED照明是市场改变者，或又一个“绿色徽章”？

LED照明离主流照明还有很长一段路要走，虽然市场上已经开始出现种种外形尺寸和设计的早期固态照明产品。在这个时候，设想未来几年中LED将如何发展，哪些功能和应用可以被证明能够吸引消费者还为时过早。让我们来看看这场游戏的现状。

48英寸的LED T8管日光灯就是一个有趣的例子。虽然它并不打算作为传统上需要镇流器的荧光灯管的简单替代品，但是这个产品仍然指向荧光灯照明市场。

每个18W的管子由三排96颗LED组成。外两层是冷白光，里边一层是暖黄白光。分布式电源向下沿着双层LED PCB板的背面钉在一起，以达到指定的长度。管子光通量为820lm，或大约46lm/W，同规格高品质的T8荧光灯管可达到100lm/W的一半。

该管子的寿命声称是50,000小时，对于LED似乎有可能，但是对整个组装件来说就有点过于乐观了。因为其中使用了大量的电解电容器，在较高环境温度下必定会降额。288颗LED排成18个并联串，每串16颗。

由于荧光灯管售价在2美元左右，并且光源质量足够好，所以对于T8管来说真正的挑战是价格。目前其标价是一般荧光灯管的30倍以上。LED产品的高价格只有当整体更换成本，同时考虑到劳动力、停机时间以及使用难度等的成本都很大时，才合理。但对于大部分应用，情况并非如此。

目前，LED灯市场仍处于起步阶段，由于高价格和不明朗的产品规划路线，需求仍不稳定。而且缺乏可信的高层引导。政府正在实施一项能源政策的专案，其中大部分都没有涉及根本问题。也就是说，大多数国家不具备足够的发电能力。要么削减能源需求，要么再在城市附近建更多电站。

更有甚者，还有其他不确定因素，例如能源价格走势如何，政府是否愿意共同合作制订一个真正国际公认的绿色能源议程（并持续下去）。显然，全球能源需求和政策将影响高能效硬件方面的投资。但是唯一明智、可持续的长期战略就是削减能源需求。

编译：Aileen Zhu

点击参考原文：LED Lighting Market Changer or Mere Green Badge

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LED Lighting Market Changer or Mere Green Badge

Malcolm Penn, Founder & CEO, Future Horizons

While LED lighting is still far from the mainstream, early solid-state lighting products are starting to appear on the market in a variety of form factors and designs. At this stage, it's too early to envisage how LEDs will develop, and what features and applications will prove attractive to consumers, over the coming years. Let's take a look at the current state of play.

The 48-inch LED T8-sized tube light is an interesting example. While it is not intended as a drop-in replacement for the traditional fluorescent tube, which needs a fixture with a ballast unit, the product is targeted at fluorescent tube light markets.

Each 18-watt tube comprises three rows of 96 LEDs; the outer two are cool-white, while the inner one is a warmer yellowish-white. The power supply runs distributed down along the back of the two LED PCBs that are stapled together to achieve the correct length. The tube emits 820 lumens, or approximately 46 lumens per watt, which is roughly half the 100 lumens per watt obtainable with the equivalent high-quality T8 fluorescent tubes.

The tube's life is claimed to be 50,000 hours, which seems reasonable for the LEDs, but a little optimistic for the assembly as a whole, given the large number of electrolytic capacitors used must be de-rated for use in higher temperature environments. The 288 LEDs are arranged in 18 parallel strings, each containing 16 diodes.

Since fluorescent tubes sell for around $2, and have a more than adequate quality of light, the real challenge is the T8's sticker price, which is 30 times more. The high price of LED products can only be justified when the overall replacement cost of alternatives, taking into account labor, downtime, and access difficulty, is greater. But for the majority of applications, this is not the case.

Right now, the LED lamp market is still in its infancy, and demand is uncertain, both due to high prices and an unclear product road map. Lacking is credible top-level direction; governments are pursuing a variety of ad hoc energy policies, most of which don't address the fundamental issue. That is, that most countries do not have enough generating capacity; either demand has to be cut, or the world must build several more power stations close to cities.

To top it off, there are undetermined variables, such as what the price of energy will be, and whether governments will collectively embrace a truly green internationally-agreed energy agenda (and stick with it). Clearly, global energy needs and policies will affect investment in energy-efficient hardware. But the only sensible, sustainable long-term strategy is to cut back on demand.