Could high-flying drones power your home one day？

Image copyrightMakaniImage caption

图片copyrightMakaniImage标题

Makani's unmanned tethered drone soars high while its propellers generate electricity

马卡尼的无人系绳无人机在螺旋桨发电时飙升

A growing number of companies believe using tethered kites and drones is a viable way to harness the stronger and more consistent high-altitude winds. Could this tech release wind power's full potential, or will it always remain a niche solution？

越来越多公司认为使用系留风筝和无人机是一种可行的方法来利用更强大和更一致的高海拔风。这项技术是否可以释放风力发电的全部潜力，或者它是否始终是一个利基解决方案？

Wind power generated five times more electricity in 2018 than in 2008, according to recent figures from the US Energy Information Administration.

根据最近的数据，风能在2018年产生的电量是2008年的五倍。美国能源情报署。

Yet it still only accounts for about 4% of the world's electricity.

然而，它仍占世界电力的4％左右。

Critics point to the fact that the wind doesn't always blow - the intermittency problem - making this form of renewable energy unreliable.

批评者指出这一事实风不总是吹 - 间歇性问题 - 使这种形式的可再生能源不可靠。

But winds at higher altitudes - above 500m (1,640ft) - blow stronger and more consistently. An influential 2012 study from California's Lawrence Livermore National Laboratory found that high-altitude winds alone could provide 100 times the global energy need.

但是在更高的海拔 - 500米（1,640英尺）以上的风吹得更强更一致。来自加利福尼亚州劳伦斯利弗莫尔国家实验室的一项有影响力的2012年研究发现，单独的高海拔风可以提供全球能量需求的100倍。

Image copyrightAirborne Wind EuropeImage caption These charts show how average wind speeds increase at higher altitudes

图片版权所有航空风欧洲影像标题这些图表显示平均风高海拔地区的速度增加

“Wind turbines have been getting bigger and bigger in a bid to access winds at high altitude,” says Udo Zillmann of trade association Airborne Wind Europe. “But that means huge, expensive towers.”

“为了在高海拔地区进行风力，风力涡轮机的规模越来越大，”贸易协会Airborne Wind Europe的Udo Zillmann说。 “但这意味着巨大而昂贵的塔楼。”

• Reaping the wind with the biggest turbines ever made

  用最大的涡轮机重新获得风力

So hi-tech drones and kites are now becoming accepted, lower-cost supplements, he argues.

他认为，高科技的无人机和风筝现在正在被接受，成本更低的补品。

“Airborne wind energy is a minimalistic version of a turbine, incorporating only the necessary elements: a blade and a tether measuring a few centimetres in diameter,” he explains.

“空中风能是涡轮机的简约版本，只包含必要的元素：直径为几厘米的刀片和系绳，”他解释说。

Image copyrightMakaniImage caption Makani readies its kite before a test flight in Hawaii

图片版权所有.MakaniImage标题Makani在夏威夷进行试飞前准备放风筝

“These systems require between 1% and 10% of the materials used to construct a turbine and can also be grounded if required, for example to ease the passage of migrating birds.”

“这些系统需要1％到10％的材料用于建造涡轮机，如果需要，也可以接地例如，为了缓解迁徙鸟类的迁徙。”

Makani, part of Google's parent company Alphabet, is one of the companies working in the high-altitude wind space.

马卡尼是谷歌母公司Alphabet的一部分，是在高海拔风力空间工作的公司之一。 / p>

Its huge prototype kite is tethered to the ground and guided in loops by flight computers that use GPS and other sensors.

它巨大的原型风筝拴在地上，由使用GPS和其他传感器的飞行计算机循环引导。

As the kite completes its loops, rotors on the 26m (85ft) wing spin in the wind, powering generators to produce electricity down the tether to the grid.

风筝完成其环路，26米（85英尺）翼上的转子在风中旋转，为发电机提供动力，沿着系绳向电网发电。

Makani began testing its current prototype, which is designed to produce up to 600 kilowatts of electrcity - enough to power about 300 homes - in 2015.

马卡尼开始测试其现有的原型， 2015年，它的设计能够产生高达600千瓦的电力 - 足以为300个家庭提供电力。

Image copyrightAiborne Wind EuropeImage caption Udo Zillmann thinks wind drones will be a crucial part of our renewable energy future

图片copyrightAiborne Wind EuropeImage标题Udo Zillmann认为风力无人机将成为关键部分我们的可再生能源未来

And in partnership with energy giant Shell, it is about to trial a new offshore system mounted on floating buoys.

与能源巨头壳牌公司合作，它即将试验一种安装在漂浮浮标上的新型海上系统。

“We plan to mount Makani's kite on a small spar buoy moored with a synthetic line and gravity anchor,” says the firm's chief executive, Fort Felker.

我们计划将Makani的风筝安装在一个小型晶石浮标moo上该公司首席执行官Fort Felker表示，红色是合成线和重力锚。

“This is possible because Makani's kites are 90% lighter than turbines of a similar power rating. It's an exciting technical challenge.”

“这是可能的，因为Makani的风筝比类似额定功率的涡轮机轻90％ 。这是一项激动人心的技术挑战。”

Flying energy-capturing kites or drones offshore makes sense from a regulatory point if view, given that some can travel 600m in each direction.

如果能看到有些人可以在每个方向行进600米，那么从海上观察飞行能量捕获风筝或无人机是有意义的。

“You need a huge area to operate even one device, which is one reason many companies are looking offshore,” says Mr Zillmann.

“你需要一个巨大的区域才能操作一台设备，这是许多公司在海外寻找的原因之一，”Zillmann先生说。

There are also a number of companies working on ways to use wind power-generating drones over land, though.

不过，也有很多公司正在研究如何在陆地上使用风力发电无人机。

Swiss start-up Skypull, for example, has developed an autonomous drone that can fly as high as 600m - about three times the height of a traditional wind turbine.

瑞士初创公司Skypull开发了一种自动无人机可以飞行高达600米 - 大约是传统风力涡轮机高度的三倍。

Its current prototype is a rigid wing, multi-copter “box-wing” drone that can take off and land by itself, with no need for a launcher or ground wind.

它目前的原型是一个刚性机翼，多直升机“箱翼”无人机，它可以自行起飞和着陆，无需发射器或地面风。

Image copyrightSkypullImage caption Skypull's “box-wing” drone takes flight on its winch

图片copyrightSkypullIma标题Skypull的“盒翼”无人机在其绞盘上飞行

The take-off is battery powered, but once in the air the battery is recharged every time the kite loops back down towards the ground.

起飞是由电池供电的，但是一旦在空中，每次风筝回来时电池都会重新充电

“Once it has climbed to operating height, the drone transitions to kite mode by turning 90 degrees from the upright position, and generates traction on the tether, which is attached to a winch that is linked to a generator,” explains Skypull chief executive Nicola Mona.

一旦爬升到操作高度，无人机从直立位置转过90度就会转换到风筝模式，并在系绳上产生牵引力， Skypull首席执行官Nicola Mona解释道，它与一台与发电机相连的绞车相连。

“It's a system that enables us to fly between 200m and 600m above the ground in any location.”

“这是一个让我们能够在地面以上200米到600米之间飞行的系统。 Mona先生承认，早期使用可能仅限于较小的项目，但他相信Skypull系统有朝一日可用于满足大规模能源需求的任何地点。”

“In the mid-term, I can see our technology being used for remote off-grid systems, such as mining operations and disaster relief projects,” he says.

“在中期，我可以看到我们的技术被用于远程离网系统，例如采矿作业和救灾项目，”他说。

“In the longer term, however, I foresee larger wind farms capable of generating up to 100MW [megawatts] of power.”

“从长远来看，我预计更大的风电场能够产生高达100兆瓦（兆瓦）的电力。”

Other onshore high-altitude wind players include Altaeros Energies, a Massachusetts-based technology company that attracted investment from Mitsubishi Heavy Industries in 2015.

其他陆上高空风力发电机包括Altaeros Energies，这是一家总部位于马萨诸塞州的技术公司，于2015年吸引了三菱重工的投资。

Its Buoyant Airborne Turbine involves a helium-filled shell that lifts a wind turbine to 600m above ground, and aims to supply power, telecommunication, and other services to the billions of people around the world who live without reliable electricity and internet access.

它的浮力式机载涡轮机包括一个充满氦气的外壳，将风力涡轮机提升到地面以上600米，旨在为全世界数十亿人提供电力，电信和其他服务。电力和互联网接入。

Image copyrightAltaerosImage caption Altaeros' Buoyant Airborne Turbine generates electricity and provides internet connectivity

Ima版权所有AltaerosImage标题Altaeros的浮力式机载涡轮机发电并提供互联网连接

The big drawback of such systems is that they don't generate that much electricity compared to current turbines. Makani's huge propellered drone, for example, produces about 20 times less electricity than the largest offshore turbines currently being developed. These can produce up to 12MW (megawatts).

此类系统的一大缺点是，与现有的涡轮机相比，它们不会产生那么多电力。例如，马卡尼巨大的无人驾驶无人机产生的电力比目前正在开发的最大的海上风力发电机少20倍。这些可以产生高达12MW（兆瓦）的电力。

So you would need hundreds of them to produce enough electricity to power a small city, for example.

例如，你需要数百个才能产生足够的电力来为小城市供电。

This is why Mr Zillmann sees them more as “the next step in the digitalisation of the traditional windmill”, and expects them to be used in parallel with traditional wind turbine towers “for a long time yet”.

这就是为什么Zillmann先生将它们视为“传统风车数字化的下一步”，并期望它们与传统的风力涡轮机塔架同时使用“很长一段时间”。 / p>

But renewable energy - wind, solar, hydro - is “definitely capable of meeting the entire world's energy needs, and drones can help us achieve this”, he concludes.

但可再生能源 - 风能，太阳能，水能 - “绝对能够满足全世界的能源需求，无人机可以帮助我们实现这一目标”，他总结道。

Follow Technology of Business editor Matthew Wall on Twitter and Facebook

在Twitter和Facebook上关注商业编辑Matthew Wall