Renewable Roundup: 25.4%-Efficient solar cells

  • Published on June 25th, 2020

The first “practical” solar cells came out in 1954 with 6% efficiency. Research cells have now reached 44.5% efficiency, while 23% was the best in commercial products last year. Now we are at 25.4% with a new product about to go into production. It combines two established technologies, offering the best of both.

IBC heterojunction solar cells - 25.4% efficient (Photo by Suhaila Sepeai)
IBC heterojunction solar cells – 25.4% efficient (Photo by Suhaila Sepeai)

By Mokurai

I could dive deep into the technology, but I won’t here. Our concern in these Diaries is not geekitude, which you can look up elsewhere, but fighting anthropogenic global warming.

Suffice it to say that lots of bright people are getting funded to think of lots of ways to make better solar cells, and that a few of those ways turn out to be commercially viable, leading to greater efficiencies, longer life, and other virtues at ever lower cost, with significantly expanded markets each time.

European consortium bid to bring 25.4%-efficient heterojunction-IBC solar cell into mass production

The EU-funded Nextbase project aims to manufacture heterojunction, interdigitated back-contact solar modules for less than €0.275/W. Solar panels featuring the Nextbase cell tech are expected to have a conversion efficiency of 23.2%, according to the European Commission.

That is, complete panels will have slightly lower total efficiency than the cells used in them, due to losses in wiring, conversion to AC, and so on.

A statement issued by the commission said production equipment supplied by Swiss HJT company Meyer Burger would be used to produce 25.4%-efficient HTJ-IBC solar cells on a commercial scale.

That efficiency figure would constitute “a European record for an industrially-feasible version of IBC-SHJ [silicon heterojunction] technology,” said project coordinator Kaining Ding, of German research center Forschungszentrum Jülich GmbH, which is a partner in the initiative. Ding added: “The current laboratory world record for a silicon solar cell is 26.7%, which was also based on the IBC-SHJ concept but was very expensive to make. Our approach is close to the optimum level.”

An old engineering rule says

Good, cheap, and fast [or powerful]: pick two.

Timeline of solar cells

The photoelectric effect was observed in 1839, and explained in Einstein’s 1905 paper in quantum terms.

  • 1913 – William Coblentz receives US1077219, “Solar cell.”
  • 1950s – Bell Labs produce solar cells for space activities.
  • 1954 –  On April 25, 1954, Bell Labs announces the invention of the first practical silicon solar cell.[8][9] Shortly afterwards, they are shown at the National Academy of Science Meeting. These cells have about 6% efficiency. The New York Times forecasts that solar cells will eventually lead to a source of “limitless energy of the sun.”
  • 1957 – Hoffman Electronics creates an 8% efficient solar cell.
  • 1959 – Hoffman Electronics creates a 10% efficient commercial solar cell, and introduces the use of a grid contact, reducing the cell’s resistance.
  • 1960 – Hoffman Electronics creates a 14% efficient solar cell.

And so on down to today.

Solar cell

Adjusting for inflation, it cost $96 per watt for a solar module in the mid-1970s. Process improvements and a very large boost in production have brought that figure down 99%, to 68¢ per watt in 2016, according to data from Bloomberg New Energy Finance.[24]Swanson’s law is an observation similar to Moore’s Law that states that solar cell prices fall 20% for every doubling of industry capacity.

€0.275/W is thus right on track.

What are the most efficient solar panels on the market? Solar panel cell efficiency explained

Most solar panels are between 15% and 20% efficient, with outliers on either side of the range. High-quality solar panels can exceed 22% efficiency in some cases (and almost reach 23%!), but the majority of photovoltaic panels available are not above 20% efficiency.

Until now.

Here are the top five best solar panel manufacturers in 2019 ranked based on the highest efficiency solar panel they have to offer:

  1. SunPower (22.8%)
  2. LG (21.7%)
  3. REC Solar (21.7%)
  4. CSUN (21.2%)
  5. Solaria (20.5%)

This is the most efficient solar panel ever made

Scientists have developed a solar cell that is capable of converting direct sunlight into electricity with 44.5 percent efficiency — making it, potentially, the most efficient solar cell in the world. Current solar technology only converts electricity with a maximum efficiency of about 25 percent. The impressive cell works by stacking multiple layers of solar hardware into a single cell, each of which absorbs a different aspect of the solar spectrum.

The prototypes are extremely expensive. We know that we can bring costs down substantially, and we know that we can afford to use them before they get to be quite as cheap per watt as less efficient cells, because they can supply the same power from fewer panels, or more power from the same area, take your pick.

Watch this space.

(Crossposted with DailyKos.)

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