This post is a reply to this tweet I saw. In case it gets deleted, San Francisco implemented a bylaw requiring all new construction to have solar panels in use. Sean is asking why Calgary doesn't have this when we have over 200+ days of sun (we actually have roughly ).
I want to present very important information, speaking as an electrical engineer. The main arguments for solar panels is that it is good for the environment, is renewable energy (the sun) and that it is good for our pocket books in the future. My goal is to share information about solar panels, as an engineer, to show that solar panels don't live up to the argument for it.
Why use solar?
It's best to start by listing out the important points raised for why we should be using it. It isn't all just environmental. Whether you or I disagree (ethically or morally) isn't the intention of this post. The argument and reasoning for doing something is a totally different discussions and something I'll reserve for a future post.
Good for the environment
Allows end users independence from the grid
Less loss in distribution (as it is local)
Improves grid security
Creates jobs and stimulates the economy
It's important to take away that there is a hierarchy in the reasoning. The main argument is that it is ‘good' for the environment. The rest are merely features, but described as benefits. This is a concept in . This is brought up to make sure that the main argument is always returned too because disproving the ‘features' doesn't change the argument. If all the features are proven false, a proponent will support the idea.
Why energy?
Before I can speak of solar energy, I have to look at energy in general. I would also like to get deeper by asking why why? Why do we do anything?
Life just isn't is. Living things have a dichotomy; existence or non-existence. This is true of all living things whether a plant, animal or human being. Existence requires action, in particular the action of seeking out the values that make life possible and the values to make existence worth living. There's no guarantee that any living thing will get all the values (if any) they seek out, but to choose life, is to choose the action.
All living things have different means of accomplishing this action. A plant operates automatically, according to it's nature, to get the values of sunlight, water and minerals. A plant will wrap around objects in it's way to get better sunlight, though there is no guarantee it will get it. Animals seek out values through instinct. A fox just knows that a rabbit is a delicious meal. A fox is also born with claws, the attributes of speed and has fur to keep warm. Humans are born into this world without claws, fur or necessary instinct to survive. There are no instincts that say the berries on the tree are good or poisonous. Humans only means of obtaining the values of life is through their mind and rational thought. Humans think and than act on their thoughts.
This metaphysical injection of information may seem irrelevant, but it's important to state why man acts. Man acts for the values of life and the values that make life worth living. And man acts based on rational thought. Environmentalism and solar panels walk hand and hand. Environmentalism doesn't hold the metaphysical understanding I stated, but one that places value in the environment for it's own sake - and in some cases an anti-man ideology (that the ideal environment is one where humans never existed).
The environment in and of itself doesn't have value. The value of the environment is one in context of the value to man. This thought process might not change much of the arguments that follow in this essay, but this distinction is important. Man must think and act for the betterment of man (values of life and values worth living for) and not for the ‘value of the environment' at the expense of man.
Do solar panels create jobs and stimulate the economy?
There are two ideas here, so let's deal with them one on one.
Does it create jobs? Yes. Anything that exists and requires work, means there will be jobs. But jobs, in and of themselves, are not necessarily good/bad things. Productive output is the measure of the VALUE to the economy. So if 10,000 people are needed to do what 2000 people can do - this is a net loss to society. The value to the economy (and in away - the stimulating) is measured by productive output per person. You can also look at this from a spending perspective as a consumer. Are you better off spending $20 for something that you used to buy for $10? Of course there will be jobs, but when you attach an output of energy per job you see that we are getting far less.
Does it stimulate the economy? This belief comes from a false look at economics. Many people believe the economy is driven simply by consumption and the simplest way to get there is to have people working. Therefore, as long as someone has a job that pays a decent amount, it's stimulating. No one is really interested in discussing the output of this work. Getting paid $25/hr to dig useless holes creates economic stimulus because someone has $50k a year in income. What is produced by work is wealth and really derives the value of the economy.
What happens to the economy when paying more money and more people to produce the equivalent amount of output? It's a net loss for the economy (which is everyone in the economy). The "
Do solar panels create grid security?
Grid security, in this context, means decentralized. We'll have more people with solar panels on their roof and we become less dependent on larger utility maintenance/down-time.
I'll concede, in theory, that decentralizing the grid would help with grid security. In practice, there are several issues that are overlooked by the arm chair engineer. First lower voltage infrastructure and secondly issues with sinusoidal purity.
Lower voltage infrastructure: The actual utility connection to your house and to your neighborhood is lower voltage. The connection to your house is 120/240V single phase. Your neighborhood may be at a higher voltage, depending on the grid dynamics, but still significantly lower than high voltage infrastructure. Often streets within a neighborhood are still fed at single phase.
Power = Voltage x Current
To deliver the same amount of power, the lower the voltage - the higher the current.
Voltage = Current x Impedance
Therefore
Power = Current^2 x Impedance
Impedance (resistance) in the transmissions has a pivotal play in the actual power delivered. The impedance, in and of itself, isn't what leads to power - just the voltage at which we receive the power.
Simplifying these equations, with lower voltage infrastructure we have more resistive (impedance) wiring to homes and to the neighborhoods. This means that there is a high degree of loss in transmission when compared to high voltage output and infrastructure. As per the formula above, higher voltage means lower current and therefore less loss.
Sinusoidal purity: The grid operates at many different voltages throughout the province/country. The one that is constant is that it is a three phase system, operating at 60Hz and each phase shifted by 120 degrees (for those of you that remember trigonometry). Most of the grid is AC (alternating current), but in some applications DC (direct current) is used to prevent losses (DC over long distances and at very high voltages has been shown to be a good way to reduce transmission losses). The electricity in your home is AC.
Solar panels produce a DC output and in order for this power to be put back on the grid (or to use standard electrical items in your home) it must be converted to a 60Hz sinusoidal AC wave. This is done with a component known as a power inverter. The problem (not with inverters), but DC is that we don't have a way to make a pure sinusoidal wave. In basics, we can make a square wave that is 60Hz, looks like . To make it more closely resemble a sine wave, we use more squares producing something like .
The graphs shown above are all well understood sinusoidal waves as a function of time. You can't identify issues with it as a function of time. As a function of frequency we see something known as . I'm getting a lot more technical than I was intending with this article, but I promise I'll make my point. The rising edges and falling edges of the created wave (the vertical runs) are composed of many high frequencies. Sparing the math, with a three phase system with each phase 120 degrees offset create overlapping harmonics - in particular the 3rd, 5th and 7th harmonics. These imperfections and significant current loads ripple out onto the grid distorting it.
Fixing these harmonics requires expensive power electronics to weasel them out and other methods (such as the delta configuration of a transformer). For one solar panel in your neighborhood, it won't matter at all. Most of it will die in resistance - as pointed out with the lower voltage infrastructure point. But as more and more people start using solar panels these harmonics will be inescapable, especially the further you are from harmonic mitigating devices. What you'll be left with in your neighborhood are power quality issues which can damage what you have plugged in. The only place that could probably avoid it is truly high voltage bussing areas, such as the "" in downtown Calgary, but work to keep power quality sound would be required.
Do solar panels have less loss because they're local?
Well, if you're thinking of a purely autarchic solar system, sure. Transmissions losses are lower because you're closer. For feeding the grid, there is higher losses compared to utilities due to the points illustrated earlier.
With an autarchic system there are losses. Most people aren't using the energy created in real time. Most people need to capture the power and store it for later use. The act of storing this energy results in a loss of 50% of total available. Much of this is dependent on the chemistry of the battery. Many people just view a battery, as just a battery, but it has specific characteristics of how it needs to be charged - and the variableness of solar output is always an issue.
There are also losses in the power inverter that are substantially larger when using a simple consumer good versus a utility grade item.
Do solar panels create independence from the grid for the end user?
Yes. At an expensive cost and lost conveniences (like all the power needed whenever needed), but yes.
Are solar panels good for the environment?
This is the big question and the most important question to answer. I'm going to address this from both a substance perspective and an energy perspective.
Energy
It needs to be said that it takes more energy to make, build, deliver, install and recycle a panel than it will ever produce over it's life. There is a single study that claims , but this study contains epistemic issues - though that doesn't stop .
An issue is to call into question what knowledge one can derive from such a study. The way a study is conducted and the way it works is the basis of figuring out what knowledge can be derived. This is philosophical territory and a place where scientists are rarely perfect.
Let's review a few points from the studies abstract:
This paper develops a number of unique data sets, namely the following: calculation of distribution of global capacity factor for PV deployment; meta-analysis of energy consumption in PV system manufacture and deployment; and documentation of reduction in energetic costs of PV system production. These data are used as input into a new net energy analysis of the global PV industry, as opposed to device level analysis. In addition, the paper introduces a new concept: a model tracking energetic costs of manufacturing and installing PV systems, including balance of system (BOS) components.
Read this part, "… opposed to device level analysis." They're taking their own "unique data sets" instead of actually looking at solar panels. That's suspect. They take unique data points, instead of panel related points, then they use this data of a "new net energy analysis" and finally plugged into a model. You'll find that they aren't analyzing actual energy. The actual study doesn't produce the knowledge to reach such a conclusion.
The other issue I find is with the conclusion itself. Electricity produced by solar panels is greater than that of the electricity required to create the panel. If we were to assume the study was sound, I'm left wondering - why just electricity as the measure? Panels are shipped in trucks that run on fuel, not electricity. Panels are made of rare earth metals (will go into more detail in the environmental rebuttal) that require huge amounts of energy to extract. Panels also will require recycling, which requires energy. None of this energy use is added to the panel when electricity to build is the only metric. It takes X amount of electricity, Y amount of oil barrels, Z amount of gasoline to have a fully operational panel.
Environment
The environmental aspect to all this is what I find the most strange, especially with the measurement of environmental impact. There is an incomplete standard when it comes to comparison to other means of producing energy. With solar, we merely look at the input and output. Input: sun, always there, good and Output: electricity. Compare that to coal (Input: coal, mined, requires energy to produce, byproducts and Output: electricity) or Nuclear (Input: nuclear reaction and Output: electricity and nuclear waste).
If you haven't picked up on it, solar has a very simplistic standard, which is energy out. The other forms of energy are viewed more broadly, encompassing more of the energy production. Proper comparisons in energy is the total summation of all requirements of energy production - not the final product that yields the actual energy.
Solar panels are made of rare earth metals. Rare earth metals are not abundant and difficult to extract. The process of extraction produces byproducts and these byproducts are a reality of production. Just as there is byproducts with fracking, nuclear fission and heating your house - the same is true for the materials required for the production of solar panels. These byproducts are . It's important to note that these radioactive byproducts are different than those of a nuclear reaction. At least with a nuclear reaction this byproduct is captured and contained in the core. With extracting minerals it can't be fully captured and contained.
Recycling solar panels is again an energy intense process to recover rare earth metals. The same radioactive byproducts in production are produced in this process as well.
As you can see, it isn't as simple as looking at the energy of solar to view the ‘environmental value'. This discussion is quite similar to that of lightbulbs. People see a 60W incandescent and conclude a 12W compact fluorescent and 10W LED is more environmentally friendly - based totally on watts. Fluorescent and LED both have rare earth metals, and fluorescent contains mercury (toxic for human life).
I'm not saying that solar panels are better or worse than other forms of energy production. What I am saying that it is far more complex of a question than what most people assume. Objectively speaking, hydro is the most environmentally friendly electricity produced (also the cheapest), assuming you discount the value of things like fish. Even though this is by far the best form of energy production solar and wind seem to be the defacto winners. Wind is another discussion and I have a negative view of it as well.
The Reality of the Future of Energy
The need for more energy in the foreseeable future is real. If people want cars to plug in, transit busses and trains run on electricity. Moving away from gasoline and oil doesn't change the fact that people move that demand onto the electricity grid. We need more power.
I reject the notion that solar and wind can do this. They're poor energy sources. They're expensive, have short lifespans, variable outputs and (in the case of wind) require a lot of maintenance.
Climate change is the big motivator in changing the way we produce energy. I don't think we really have to deal with it the way people look at it, but if we are going to deal with it - shouldn't we do it properly?
If we want to meet the extraordinary energy requirements of the future and reduce greenhouse gases, nuclear is the best option. One large facility can near provide the entire electricity to a province like Alberta. A nuclear plant should have a lifespan 4 times that of solar and wind. A nuclear plant will have less maintenance per unit of energy than something like wind. And lastly the byproduct of nuclear can be contained.
As good as nuclear is, it is rarely talked about positively. For very apocalyptic prophecies of climate change proponents, they seem to want to implement the snails pace of electrical change with solar and wind. Compound this with the very , no one is really trying to solve the climate change problem - especially the proponents.
Conclusion
Let's reiterate the main discussion point, solar panels being used in urban settings. One shouldn't use a solar panel because it requires more energy to create than it actually produces over the life. It's made of rare earth metals that produce radioactive byproducts. It simply isn't as environmentally friendly as people like to think.
Using a solar panel in a remote cottage or something along these lines makes sense - but it makes sense economically or convenience. It isn't like we can put solar panels on every building, yada yada yada, live happily ever after.
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