Green, ethical, energy issues in the news

70sbudgie

When people use phrases like:
The energy collected from the sun would then be beamed to Earth where it is converted into electricity.
It makes me wince.

The principle of solar energy in space isn't new - it is how most satellites are powered and why they shine (it is the solar panels reflecting). They are also very efficient because the temperature is pretty stable. 

The big issue is getting the energy to earth. 

I can only think of high energy light and most of the electromagnetic spectrum isn't capable of carrying enough energy, far enough. It would have to be something like a giant x-ray. Which sounds pretty scary to me!

Also, won't a geo stationary satelitte be in the earth's shadow for part of the day?

Martyn1981

I watched a programme about 15yrs ago that tested this idea of beaming energy from space. Or to be more exact, they tested the beaming part by sending microwave energy 92 miles between two islands in Hawaii, to simulate the problems of transmitting energy from space, through our atmosphere.

The programme was one of a series, where large ideas were tested (on a small scale) to see if they are viable, here's a link to the Wiki page, I thoroughly enjoyed the series. And below a news item on the space PV experiment:

Researchers Beam 'Space' Solar Power in Hawaii

The key to our energy future may be in space. A new long-range energy transmission experiment opens the possibility of sending solar energy from space to earth.

Former NASA executive and physicist John Mankins captured solar energy from a mountain top in Maui and beamed it 92 miles to the main island of Hawaii.

Tonight at 10 pm Discovery Channel will air an episode of Project Earth on the recent first-of-its-kind experiment. This long range demonstration of wireless power transmission was also a key step toward space-based solar power satellites. The team also beamed the power almost 100 times farther than NASA's major 1970's power transmission in the Mojave Desert in California.

Although the amount of power sent, 20 watts, is barely enough to power a small compact fluorescent light bulb, and most of it was lost in transmission, the system was limited by the budget not the physics. If they had been able to afford more solar panels, more phased array transmitters and a better receivers (the one they had could only receive in the horizontal direction), Mankins claims they could do much better-- possibly up to 64% efficiency.

70sbudgie

Thank you for those links, they make really interesting reading. 

I guess the bits that I take from it are: electricity generation has come a long way in the last 15 years, but space energy doesn't seem to have. Which to me, suggests a fundamental flaw somewhere. (I'm not going to try to say what as the brains behind it are clearly much bigger than mine!)

Also the irony of importing energy from space when other projects on that wiki list include solar shields, reflective clouds and other mechanisms for reducing the total energy absorbed into earth's atmosphere.

And the numbers. 20W. And up to 64% efficiency. I would love to know what has happened to this concept since then.

Coastalwatch

Afraid in my simplistic view sunbeams arrive here naturally so I'm struggling to understand the logic of interrupting them and forwarding energy on at only 64% efficiency. But maybe I'm just missing the point of it all!

shinytop

Coastalwatch said:

Afraid in my simplistic view sunbeams arrive here naturally so I'm struggling to understand the logic of interrupting them and forwarding energy on at only 64% efficiency. But maybe I'm just missing the point of it all!

Clouds and night are the problems I think.

Spies

Don't think this has been mentioned, very promising though for V2G proof of concept when balancing the grid.

https://www.current-news.co.uk/news/octopus-energy-and-national-grid-eso-hail-line-in-the-sand-moment-for-v2g-tech 

Coastalwatch

shinytop said:

Coastalwatch said:

Afraid in my simplistic view sunbeams arrive here naturally so I'm struggling to understand the logic of interrupting them and forwarding energy on at only 64% efficiency. But maybe I'm just missing the point of it all!

Clouds and night are the problems I think.

Good points ST, perhaps we need huge areas of them placed between us and the sun to deflect some of the heat away and so reduce some of the effects of climate warming.

Coastalwatch

It wasn't so much that it crashed that drew my attention but 64 days of continuous flight. But as ST previously pointed out at an altitude of 60,000 feet with few clouds to worry about there may be little need for a substantial battery!

Airbus solar airplane crashes after 64 days of flying.

https://www.pv-magazine.com/2022/08/29/airbus-solar-airplane-crashes-after-64-days-of-flying/

Coastalwatch

While some states in Oz are still powered predominantly by coal NSW is attracting a variety of renewable projects with investment totalling $29.4 Billion Aus dollars, £17.4 Billion. Think we could do with a few of those on that scale over here!

Australian ‘renewable energy zone’ attracts 17 GW of project proposals

https://www.pv-magazine.com/2022/08/29/australian-renewable-energy-zone-attracts-17-gw-of-project-proposals/

Martyn1981

Yet another 'don't hold your breath' potential wave energy breakthrough. But always worth a quick butcher's, as eventually (maybe!) one will work.

And this one is predicting a cost of generation of less than a penny a kWh (~1c/kWh), which would be great, and whilst we can't in the UK, match the US figures for PV, I suspect we do OK when it comes to coastline and waves ....... though ours do seem to like to destroy wave generation technologies.

At 100MW+ per unit, a lot of alarms are going off, and I appreciate that many will be very sceptical like myself. But I'll keep my fingers crossed and send them my best wishes, but not any hard cash.

SWEL Promises Cleanest, Cheapest Energy Ever — We’ll See

Sea Wave Energy Ltd. (they go by “SWEL,” natch) has spent the better part of the last decade developing a floating, wave-riding generator that the company claims will produce a whole lot of tidal energy for not a whole lot of money.

First shown to the world a few years and recently back in the news, SWEL’s floating wave energy device is called the “Waveline Magnet,” and it’s basically a long, modular chain of plastic floats  that are designed to sit on top of the water, lined up perpendicular to the shore (i.e., directly into the waves). As the waves pass below the Waveline Magnet, the floats follow the contours of the water, creating a sort-of “up and down” serpentine motion in the chains of floats that works on lever arms to drive low-cost electrical generators inside the spine units on both their upward and downward motions.

The best part? Waves are free — and the electricity it produces is nearly free, as well!

“One single Waveline Magnet will be rated at over 100 MW in energetic environments,” said the inventor of the device and SWEL’s CEO, Adam Zakheos, “… we can show how a commercial sized device using our technology will achieve a Levelized Cost of Energy (LCoE) less than 1¢€(US$0.01)/kWh, crushing today’s wave energy industry reference value of 85¢€ (US$0.84)/kWh.”