1. As you may have heard, a solar power system can save you money. Well, you heard right. The most common two ways of buying a solar power system are paying cash or financing. Options such as Leasing or Power Purchase Agreements (PPA) are another two ways. At Sunbrook Solar Power, we only offer cash and finance options. Although leasing or PPAs may work for some, they have their drawbacks and should only be considered after exhausting cash or financing options. One major point is that when paying cash or financing a system, you receive the federal tax credit (26% this year, 2020), and therefore you will save that much more money!
Net Metering (NEM) allows you to sell all your solar power systems exports (the power, and ultimately kWh's, not instantaneously used by your dwelling or building) for the cost of import during the time in which the export is received by the utility. In other words, if you export 1 kWh when the cost of 1 kWh imported is $0.30, you get $0.30 for that exported kWh. Because of this, depending on the solar power system size and your usage, a system will generally have a payback period of 4-9 years with a cash purchase. A financed system will pay itself off depending on the loan term, but most solar loans have no prepayment penalty, so you can shorten the payback period if your able to do so.
After the payback period is realized, most systems will have 20-25 years of production still to come, with a yearly degradation rate of only 0.4% - 0.7%, depending on the solar panels used. Over those 20-25 years, using an average system size of around 6kWs, and considering the cost of electricity going up every year, the avoided cost of electricity, is in many cases, close to or over $100,000! It is proportional to usage/system size in individual cases, but the savings are real and plentiful! One of the best investments there is.
Another monetary advantage of getting a solar system is the increased property value. In most cases, there is value in an existing system.
2. As you may have heard also, a solar power system can help the environment. Well, you heard right again. I am going to go a slightly different route here, but it relates.
Objective Truth #1: The Sun provides the Earth with an abundance of power.
Objective Truth #2: The Sun's power in a given area, or solar irradiance (Watts per square-meter or W/m²), is near 1000W/m², on a clear day at sea level on Earth's surface.
Objective Truth #3: We have a technology in solar cells, that become solar panels, to harness the Sun's power, which is conservatively 18% efficient at doing so.
Objective Truth #4: 18% of 1000W/m² is 180W/m²
Objective Truth #5: I'm tired of typing Objective Truth...
OK, here it is:
In 2016 the global energy consumption was 151.132 petawatt-hours (pWh's)
In 2017 the global energy consumption was 153.347 pWh's
In 2018 the global energy consumption was 157.063 pWh's
Taking the rise of 1.01% going into 2017, 1.02% going into 2018, using 1.03% for 2019 and 1.04% for 2020, the global energy consumption will be around 168.245 pWh's. Let's just call it 170 pWh's.
Let's quickly put pWh's (petawatt-hours) into perspective with kWh's (kilowatt-hours) since most are familiar with kWh's.
1 pWh = 1,000,000,000,000 kWh's (1 Trillion kWh's)
170 pWh's = 170,000,000,000,000 kWh's (170 Trillion kWh's)
Put another way for perspective: The age of the universe is said to be approximately 13.8 billion years old. 170 trillion kWh's is enough energy to power (14) 100 watt light bulbs for 13.8 billion years.
Ok, there is a global population of almost 7,800,000,000 people as of this writing, so we will leave it there for the calculations.
170,000,000,000,000 kWh's / 7,800,000,000 people = 21,795 kWh's/year per person
Let's call it 22,000 kWh's/year per person.
That number may seem high to some of you because that is more than most average households with 2-4 people living in them. This is everything though! The grocery store, your office building, the manufacturer, the hotel, the restaurant, the hospital, the bowling alley, etc.
Why am I showing you these calculations? To ultimately paint a picture, of how so little can go a long way in a very clean way, by answering this question:
How much LAND is needed to power global energy consumption for one year using solar panels?
Let's use the peak sun hours of the southwest United States for our solar array which has roughly on average 5 peak sun hours/day. That is 1,825 peak sun hours/year.
We already have the value of 180W/m² from above.
1,825 peak sun hours x 180W/m² = 328,500 Wh's/m² or 328.5 kWh's/m²
That means that the Sun will shine on earth's surface and 1 m² of a solar panel will produce 328.5 kWh's in 1 year.
Many solar panels are roughly 1.67 m² or 18 ft².
We need to also take into account soiling, transmission and conversion losses. Let's use 10% (.90).
328.5 kWh's/m² x 1.67m² = 548.6 kWh's x .90 = 493.74 kWh's per panel/year.
Let's call it 500 kWh's per panel/year
22,000 kWh's / 500 kWh's = 44 solar panels per person
44 x 18 ft² = 792 ft² of solar per person
792 ft² x 7,800,000,000 people = 6,177,600,000,000 ft² or 221,591 mi²
Let's call it 222,000 mi².
Since we are talking about the southwest United States, let's look at Texas.
Texas is 261,000 mi² of land.
That means that Texas is 118% the size of the giant solar array that we need. Great!
Ok, we are talking about the whole planet though. Let's break this solar array up!
ourworldindata.org has totals on consumption and a regional breakdown. It is 2018 numbers but let's carry them into 2020.
Asia Pacific = 43%
North America = 20%
Europe = 15%
CIS = 7%
Middle East = 7%
South & Central America = 5%
Africa = 3%
In kWh's that looks like this:
Asia Pacific = 73,100,000,000,000 kWh's
North America = 34,000,000,000,000 kWh's
Europe = 25,500,000,000,000 kWh's
CIS = 11,900,000,000,000 kWh's
Middle East = 11,900,000,000,000 kWh's
South & Central America = 8,500,000,000,000 kWh's
Africa = 5,100,000,000,000 kWh's
170,000,000,000,000 kWh's / 222,000 mi² = 766,000,000 kWh's/mi²
The square miles needed for each solar array looks like this:
Asia Pacific Solar Array = 96,000 mi² (Size of Oregon)
North America Solar Array = 45,000 mi² (Size of Pennsylvania)
Europe Solar Array = 34,000 mi² (Size of Indiana)
CIS Solar Array = 16,000 mi² (Half the size of Lake Superior)
Middle East Solar Array = 16,000 mi² (The other half of Lake Superior)
South & Central America Solar Array = 11,000 mi² (Half the size of Lake Michigan)
Africa Solar Array = 7,000 mi² (Size of New Jersey)
The solar arrays can be broken down further into the region's countries or states, cities, villages, buildings and dare I say....houses, to accomplish local solar power resources.
BUT, let's look at Texas again. 261,000 mi² of land. 118%.
The extra land will be perfect for mitigating module to module shading and housing much of the needed equipment. This of course wouldn't be the best approach for transmission to the different region's. But let's stick with Texas just to show the consolidated view for perspective.
The Earth, in all of it's glory, is 196,900,000 mi²
Just the land on Earth is 57,500,000 mi²
Texas (Our hypothetical solar array) is only 0.1326% of the entire earth and 0.4539% of the land on Earth.
Point is that 0.4539% of Earth's land surface can easily handle 100% of the global energy consumption in one year and again the next year, and again, and again, and again, and again, and again, and again, and again (OK, I think you get it), with a CO2 payback, conservatively, of only a few years......Talk about renewable energy!
Solar Power is a clean and abundant source and the impact on the environment is minimal, with a CO2 payback of 2-3 years depending on their production. With a 25+ year lifespan, and a minimial degradation rate/year mentioned earlier, the benefits are an objective truth. You can play a part in the percentages and reduce your carbon footprint, as well as the overall. Use this technology to your advantage, and to the Earth's!