Solar passes point of no return – in the sky, and on the ground

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For a tale of sheer inspiration and daring in the clean energy space, nothing can quite beat the extraordinary attempt by the Solar Impulse crew to fly their solar plane across the Pacific Ocean – a trip from Nagoya in Japan to Hawaii that will take five days and nights, non-stop, and which has now passed the point of no return.

I took advantage of a bout of the flu to stay in bed this morning and, for lack of anything better to do, switched on the live feed from the Solar Impulse flight, an extraordinary machine with the wingspan of a 747 and the weight of a family car, powered by solar panels and battery storage.

Being an old cricket fan, I’m used to five-day events and – with an average speed of just 30 knots – watching this flight is a little like watching grass grow. Apart from the occasional updates, there is not a lot happening – the pilot sings to himself occasionally, and the ground crew check on his oxygen supply, food and water consumption, and his yoga stretches.

The pilot asks occasionally about a line of Cirrus clouds that appear to his left. He’s worried about their shadows on the ocean 12,000 feet below. That must mean they are reasonably thick, he wonders. Don’t worry about it, they are only small patches, he is reassured by the ground crew.

Mundane though this may seem, it is an extraordinary event, an attempt at the impossible, as the crew said at the launch earlier this year. For the pilot, André Borschberg, it is one of human endurance – five days in a cockpit of four square metres, in temperatures as low as -20°C, never to leave a seat that serves also as a bed, yoga mat, and toilet.

For the technology, it is truly pushing the frontiers. The balance between generation from the panels on the solar wings, and using the charge from the batteries overnight is critical.

Each morning, the team anxiously awaits the turning point of “energy neutral positive”, a cumbersome expression to mark the point where the solar panels produce enough to charge batteries as well as fly the plane.


Around 30kW is needed to fly the plane and provide power to the cockpit and controls. Anything more is then fed back into the battery.

This morning, after the first full night-time leg, the charge from the four battery arrays got down to an average 17 per cent, but within a few hours it was up to nearly 90 per cent.

It will need a 100 per cent charge to ensure it gets through the night, during which time it glides from around 33,000 feet down to below 10,000 feet. Its daytime altitude depends on cloud cover.

As co-pilot and program initiator Bertrand Picard explained this morning, no other plane actually fills its fuel tank as it is flying (apart from those with in-flight refuellers). No other plane has ever flown so long with no use of fossil fuels.

The endeavour has been mocked by both the pro-nuclear (in a particularly nasty blog) and the coal lobbies, who deride the fact that the Solar Impulse has to wait for a “weather window” to fly; proof they say, that centralised baseload is the only option for an energy future.

Not so, this is pushing the boundaries. It is a source of inspiration of what might be achieved. And, as one commenter on their website noted: “Each propellor revolution is a nail in the coffin of the fossil fuel industry.” I hope they make it.

Hollow “victory” for US coal on mercury emissions

The US coal industry was claiming a victory overnight after the US Supreme Court rejected the Environmental Protection Authority’s move to regulate the emission of mercury and other nasty toxins from coal fired generators.

The court in a 5-4 ruling, argued that the EPA had not “costed” the proposal, although that was challenged in a withering response from the dissenting judges.

But while coal stocks enjoyed a rally on the stock market, it doesn’t change much. Around 20,000MW of coal capacity will be retired this year and next, and more in the years to follow.

Deutsche Bank analysts noted that the coal fired generators most affected by the ruling had already taken the irreversible decision to close down, and the law is not lost, it has just been kicked back to the District Court.

Deutsche Bank noted that the knock-back may be viewed as a political and sentiment win for Big Coal, it may be a loss in legal terms. That’s because the technical decision endorsed the court’s ability to apply regulations under different sections of the EPA Act, taking away the biggest objection to carbon regulations from the coal industry.

Solar households smarter and  more mobile than normal energy consumers

The Australian Energy Markets Commission has released the final report into its study into competition in the retail electricity (and gas) markets in Australia.

There are a couple of notable conclusions: One, competition is increasing as more consumers leave the big three retailers and take up with smaller retailers; and it also signals the emergence of new business models and options given the opportunities of solar and storage.

Another is that solar households seem to be, or at least think they are, better informed than other consumers. A survey commissioned by the AEMC found that solar customers appear to be considerably more active in energy markets.

Sixty one per cent of solar customers said they had switched energy retailer or plan in the past five years and 31 per cent had switched in the past 12 months. This compares with 48 per cent of non-solar customers switching in the past five years and 21 per cent in the past 12 months.

That poses an interesting problem for the big retailers, and underlines why they are keen to offer PPAs for installing solar – and in some cases battery storage – in homes in exchange for locking them into contracts for 7, 10 or 15 years.

The AWEMC said a number of factors could be contributing to the greater switching rates for solar customers, including that they are approached more often by retailers, they have greater levels of confidence to engage in the market and different motivations for switching.

Forty six per cent of solar customers said they had been approached by at least one energy retailer in the last 12 months, compared with 37 per cent of non-solar customers. They were also more active in investigating their options, with 43 per cent investigating offers or options in the past 12 months, compared with 27 per cent for non-solar customers.

Sixty three per cent of customers with solar panels rated their level of confidence to choose the right energy option or offer as seven out of 10 or higher, compared with 54 per cent for non-solar customers. Solar customers were similarly more confident than other customers in finding the right information to choose a suitable energy plan or offer.

Estimates suggest 14 per cent of all Australian households were using energy from solar panels in 2014, which is close to a three-fold increase in three years.

Giles Parkinson

Giles Parkinson is founder and editor of Renew Economy, and of its sister sites One Step Off The Grid and the EV-focused The Driven. He is the co-host of the weekly Energy Insiders Podcast. Giles has been a journalist for more than 40 years and is a former deputy editor of the Australian Financial Review. You can find him on LinkedIn and on Twitter.

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