Residential Solar Power Techniques — Can They Assist Cut back Emissions? – E/The Environmental Magazine

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The reply is sure, however solely to a restricted diploma. Performance of those techniques differ significantly and are
particularly depending on PSH (peak daylight hours per day). Here is an inventory of U.S. states with their PSH scores.

Source: https://renogy.com/blog/-what-are-the-average-peak-sun-hours-by-state/

For an space to be appropriate for solar panel use, it will need to have a PSH of at the least 4. (For reference, see https://www.solarreviews.com/blog/peak-sun-hours-explained) Ideal areas would have a PSH of 5 or extra.  Only seven states have a PSH larger than 5 – Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming.  Their mixed inhabitants is 56 million or 17% of the U.S. inhabitants.

Next are the states with a marginal PSH, which I’m calling 4 to five.  They are Delaware, Florida, Georgia, Hawaii, Idaho, Kansas, Louisiana, Montana, Nebraska, North Carolina, North Dakota, South Carolina, and Tennessee with a mixed inhabitants of 71 million or 22% of the full US inhabitants.  If, for argument’s sake, we
say that it’s possible to put in a solar power system in these marginal states half of the time.  That’s 11% of the inhabitants.

Add this 11% to the 17% who stay in states with optimum peak daylight hours, and we get 28%.  This leaves 72% of the US inhabitants residing in areas which can be unsuitable for home
solar power techniques.

Commercial solar farms can overcome the native PSH drawback by concentrating their panels in excessive PSH areas and sending the power to areas with decrease PSH.  That is the technique which we’re following. Residential solar power installations would nonetheless be helpful the place the PSH is ample and there’s no grid entry.  So, let’s now transcend residential solar power techniques and contemplate the feasibility of solar power basically.

A Commercial Solar Array

Courtesy of YSG Solar – Fair Use

SOLAR PANEL EFFICIENCY 

Here’s a hyperlink to a 2019 article in Wired Magazine that addresses solar panel effectivity…

https://www.wired.com/story/new-designs-could-boost-solar-cells-beyond-their-limits/

Summary: In the previous 20 years, solar panel effectivity has improved from 15% to 22%.  Continued enchancment is predicted, however the Shockley-Queisser Limit limits the effectivity of a single-junction solar cell to 33%.  Multi layer panels can exceed this, however they’re costly to construct.  Most analysis now’s centered on maximizing the effectivity of the single-junction cell.  R&D may lead us wherever, however for the close to future, it appears like most panel efficiencies will stay within the 20 % to 30 % vary.

PERSPECTIVE

We use energy to provide electrical energy, to provide warmth, and to maneuver autos and equipment. What appears to be usually ignored in discussions about changing fossil fuels with renewables is that it’s going to require changing all purposes to electrical energy. How a lot of our present energy demand goes into making electrical energy? Here is a hyperlink to a report from the IEA (International Energy Agency).

https://www.eia.gov/outlooks/aeo/data/browser/#/?id=15-IEO2019&cases=Reference&sourcekey=0

The information present that, in 2019, a grand complete of 187,000 TWh (terawatt-hours) of electrical energy was used, however that 51,000 TWh of this was wasted within the warmth loss concerned in producing electrical energy by burning fossil fuels.  This leaves a helpful complete of 136,000 TWh, 25,000 (18 %) of which was used as electrical energy.  Ten % of electrical energy was produced by solar energy. That implies that solar power is now solely offering 1.8 % of the world’s energy.

The excellent news is that, since renewable energy manufacturing generates no warmth waste, we won’t have to exchange the 51,000 TWh of energy from fossil gasoline combustion.  The unhealthy information is that, even when renewables produce all electrical energy, we are going to nonetheless be confronted with changing the remaining energy from fossil gasoline combustion. Add to this the necessity to construct a world energy storage capability and you’ve got a trifecta of challenges:  energy manufacturing, energy storage, and energy use.

BUILDING THE SOLAR PANELS

Let’s simply contemplate the energy manufacturing problem.  With nuclear power presently producing 9,000 TWh and renewables presently producing 32,000 TWh, 94,000 TWh of fossil-fuel generated energy is left.  This quantity will enhance as demand will increase, however to maintain issues easy, we’ll spherical it to 100,000 TWh.

According to an article right here:

https://www.solarreviews.com/blog/how-much-electricity-does-a-solar-panel-produce a 370-watt solar panel in Arizona produces 2.7 KWh of electrical energy a day or simply beneath 1,000 KWh of electrical energy per 12 months.  If we divide 100,000 TWh by 1,000 KWh, we get 100 billion, which is the variety of solar panels we are going to want.  To corroborate this calculation, I discovered one other article that did the identical factor.  Here is the hyperlink:

https://www.axionpower.com/knowledge/power-world-with-solar/#The_Facts

According to this text, it could take 50 billion 350-watt solar panels occupying 115,000 sq. miles, an space a bit larger than your complete state of Arizona.  This is simply half the variety of panels I calculated, however the article was solely addressing electrical energy whereas I used to be addressing all energy demand.

The EIA reveals international electrical energy demand of 25,000 TWh or about one fourth of the 94,000 TWh that’s the complete energy we’d must be changed with solar. Using this text’s calculations, and adjusting for complete energy and never simply electrical energy, the worldwide requirement is 4 instances 50 billion or 200 billion. It’s nonetheless a really massive discrepancy, however we’re within the 100 billion to 200 billion vary so it’s shut sufficient for presidency work. Let’s use the 100 billion I calculated as a midpoint.  That would deliver the land required to 230,000 sq. miles, an space almost the dimensions of Texas.

Let’s contemplate a number of the parts utilized in constructing solar panels.

Aluminum:  Roughly 20
kilos of aluminum are utilized in manufacturing a solar panel.  One hundred billion solar panels would require one billion tons of aluminum – fifteen instances the present 65 million tons of aluminum produced globally every year.

Here are hyperlinks to 2 articles that debate the issues that aluminum presents within the manufacture of solar
cells.

Solar needs aluminum, but the metal has a carbon problem

https://www.sciencealert.com/solar-panel-boom-s-demand-for-aluminium-is-a-big-carbon-problem

Aluminum is an considerable ingredient, however producing it requires burning a whole lot of coal, and so it considerably provides to atmospheric CO2.  Producing one ton of latest aluminum generates 17 tons of CO2.  One billion tons of latest aluminum would generate 17 billion tons of carbon dioxide.  This is almost half of the present international annual emissions. Research is underway to search out cleaner methods to fabricate aluminum.

Silver:  It presently takes about 20 grams of silver to construct a solar panel.  I discovered this text that discusses  the challenges this presents to the solar power business. Here’s the hyperlink:

https://seekingalpha.com/article/4044219-not-enough-silver-to-power-world-even-solar-power-efficiency-to-quadruple

Using the solar panel space as the idea for calculation, the creator comes up with 5.62 million tons of
silver.  Using my weight per panel methodology, I got here up with 2 million tons of silver.  I’ve not been capable of decide why there’s a distinction, however we’re on the identical order of magnitude and, for the reason that world’s present recognized official recoverable silver reserves is estimated to be lower than 600,000 tons, it’s a moot level.  Research continues on methods to construct environment friendly solar panels with out silver, but when that’s not profitable, the effectivity of utilizing silver must enhance by two orders of magnitude to make it possible.

Steel:  Here is a hyperlink to an article in regards to the metal necessities of solar panel manufacture.

https://corporate.arcelormittal.com/media/case-studies/steel-is-the-power-behind-renewable-energy

It takes 35 to 45 tons of metal to construct a one-megawatt solar plant.  We’ll name it 40 tons.  The plant would require about 2800 solar panels rated at 350 watts, which implies that every panel would have about 28 kilos of metal.  You would want 1.4 billion tons of metal to construct 100 billion of those solar panels, which is three quarters of the full international manufacturing of metal in 2021.

Glass:  There are about 44 kilos of glass in a solar cell.  You would want 2.2 billion tons of glass
to construct 100 billion solar panels.  According to a report right here <https://www.iyog2022.org/images/files/77-economicsiyog-200925.pdf> the annual international
manufacturing of glass in 2022 (The International Year of Glass) is predicted to be
84 million tons.  The glass required to provide 100 billion solar cells is 25 instances that quantity.

Although technical innovation will probably scale back these numbers, they’re so giant to start with that it does
not appear possible, particularly when the required timeframes are factored in. According to the IPCC, we should scale back international emissions by 50% by 2030 and eradicate them completely by 2050.

DEGRADATION

The solar energy business says that the present helpful lifetime of a solar panel is 25 to 30 years, however that
doesn’t imply that the panel stops producing energy, simply that power manufacturing has degraded to the purpose that solar energy firms wish to substitute them with extra environment friendly panels, and since not changing them implies that extra land is required and that will increase prices.  Research might end in methods to delay
the lifetime of solar panels and retire them in 30 to 40 years as an alternative of 20 to 30. But we’d nonetheless want to start out constructing the following spherical of solar panels earlier than they’re retired as a result of we must compensate for the degradation of the panels nonetheless in use.

WASTE DISPOSAL

Here is a hyperlink to an article within the Harvard Business Review entitled: “The Dark Side of Solar Power”…

https://hbr.org/2021/06/the-dark-side-of-solar-power

It describes the gargantuan waste drawback that the decommissioning of solar power crops will entail.  It isn’t
simply the amount of the waste, however the toxicity of a few of it, which, due to the huge scale, might be substantial even when only a small % of the full.

FORECASTS

What is required isn’t just a discount in using fossil fuels.  We have to eradicate them completely by 2050 with a purpose to cease the buildup of greenhouse gases within the ambiance.
But no projection comes near this.  Here is a hyperlink to a report by Statista:

https://www.statista.com/statistics/238610/projected-world-electricity-generation-by-energy-source/

The graphs reveals that renewable progress will cowl the expansion in demand, however that it is going to be unable to cut back
the present stage of fossil gasoline consumption – a stage that’s placing 40 billion tons of CO2 into the air every year.  Over the following 28 years, that can quantity to over one trillion tons of extra CO2 added to at this time’s present cumulative emissions of 1.5 trillion tons since 1751 (however principally since
1960).  That is a two-thirds enhance in cumulative emissions.

Here is a hyperlink to a forecast by the EIA (the US Environmental Information Administration).

https://www.eia.gov/outlooks/aeo/data/browser/#/?id=15-IEO2019&cases=Reference&sourcekey=0

This forecast is much like Statista’s however, as an alternative of fossil gasoline manufacturing remaining stage, it’s projected to extend by 25%.  Renewable manufacturing is predicted to nearly double, from 38,000 TWh to 74,000 TWh.  Even with this progress, nevertheless, renewables are usually not anticipated to even cowl the extra demand, which is why fossil gasoline consumption is predicted to extend.

My private hypothesis on that is that the affect of the deteriorating local weather may have a detrimental affect on inhabitants progress and financial exercise, leading to a decrease than forecast demand for
energy.  Nevertheless, with out unprecedented international cooperation and energy, we are going to nonetheless be burning huge quantities of fossil fuels and persevering with to worsen the adversarial local weather results we’re already experiencing.

OTHER OPTIONS

The solely different choices we now have are wind and nuclear.  Wind is beset with lots of the identical issues that we see with solar – the massive infrastructure required, the restricted lifetime of the services, emissions from building, and daunting waste disposal points.

I believe we do have a possibility with nuclear if and when it emerges from the populist and political doghouse it has been in for the previous 4 a long time, however nuclear crops are costly and
take time to construct.  Nuclear power presently generates about 8,000 TWh yearly.  This is forecast to develop to 11,000 TWh by 2050, however this quantity could possibly be significantly bigger if a significant international effort have been undertaken to construct reactors. There are presently 440 working nuclear reactors on this planet.  If we doubled that by 2050, which might entail not simply constructing new crops but additionally changing these due for decommissioning, we might double energy manufacturing to 16,000 TWh.  This is a major quantity, however far quick of what’s required
to eradicate the projected 181,000 TWh of energy which the EIA predicts will nonetheless be produced by fossil fuels in 2050.

CONCLUSION

Renewable energy can’t be produced within the portions essential to assist our present international life-style, so energy consumption must be considerably diminished with a purpose to meet the goal of eliminating fossil gasoline use.  There isn’t any in style or political will to do that voluntarily, and, even when there have been, the required discount just isn’t possible because it must be about 50%. COVID triggered an financial slowdown that diminished international energy consumption by 7 %, and that shook the world.  Can you think about our world as it’s at this time with energy consumption minimize in half? Developed international locations just like the U.S. with excessive per capita carbon footprints
must scale back their energy consumption much more.  Without a significant lower within the inhabitants, it may’t occur.  Climate Change will trigger that inhabitants discount to happen.

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