Adele and Hello - Math and a Carbon Footprint Analysis

This is my first post-startup-launch post. (If you haven't yet, check out my website and sign up for more information!)

I mentioned I wasn't going to post about the environment as much anymore, but I can't stop. I honestly started this just to show how fun math can be in looking at the number of views on Adele's Hello on youtube. It ended up with me being curious what the environmental impact was.

So today I looked at the youtube video of this song. For your convenience, here it is so you can listen to it while reading this post. Apparently it's blowing up, with an insane number of views per day.

It has 309,000,000 views and has been up for all of 20 days. Let's use some basic math to figure out how popular this song is!

Let's first see how many seconds there are in a day.

 24 \frac{hr}{day} \cdot 60 \frac{min}{hr} \cdot 60 \frac{sec}{min} = 86,400 \frac{sec}{day}

And over 20 days:

86,400 \frac{sec}{day} \cdot 20 days = 1,728,000 seconds

With 309,000,000 views in that time, we end up with 178 views initiated per second, on average, for 20 days, nonstop.

But, hold up, it takes 6 minutes for this song to complete. So that means, on average, there are:

 6 min \cdot 60 \frac{sec}{min} \cdot 178 \frac{views}{sec} = 64,000

Let's round that up to 65,000. On average, at any given time, there are 65,000 people watching the Adele Hello video on youtube. There are 15 million views per day. That's just one video on one source. In eight whole day, as many people listen to the song, on just youtube, as watch the superbowl.

If this clip keeps up (which is unlikely), she will surpass Gangam Style, with over 2 billion views, in less than 150 days. And medical stocks will go up, cause I worry that listening to this song too frequently may drive people into depression.

"But Jay," you say, "what about the energy and environment component?!?"

Adele, impacting your heart, and impacting the environment

Adele, impacting your heart, and impacting the environment

Let's figure out Adele's carbon footprint from youtube! Let's assume that Google's hosting emissions are negligible. Let's just focus on the energy used for a laptop. Let's say that it is 50W (this is conservative).

From a prior post, we know that a 100W lightbulb uses ~1kg of coal per day. So a laptop will use about 0.5kg per day. How much CO2 is this?

This is basic chem! Let's get really basic. Coal is mostly made up of carbon. So when it is burnt, every carbon molecule breaks off and bonds with O2. So we assume that all 0.5kg of carbon becomes CO2. You need to add that weight of the O2. C weighs 12 AMU (atomic mass units, pretty much the mass of a single molecule) and O2 weighs 32 AMU.

So we need to multiply the weight of coal, which is pure carbon, by the proportional increase of mass of CO2, cause each carbon atom gains O2 weight (12+32=44)

 0.5 kg-CO_2 \cdot \frac{44}{12} = 1.85 \frac{kg-CO_2}{day} for a 50 watt computer running all the time.

Also this song is 6 minutes, or 1/10th an hour, and an hour is 1/24th a day, so this song takes 1/240th of a day.

 1.85 \frac{kg-CO_2}{day} * \frac{1}{240} = .00771 \frac{kg-CO_2}{view}

Don't forget, though, that we have 15,000,000 views per day!

 0.00771 \frac{kg-CO_2}{view} \cdot 15,000,000 \frac{views}{day} = 115625 \frac{kg-CO_2}{day}

Or, you know, ~125 tons of CO2 per day. Just from Youtube and Adele. This is the generation rate of about 2000 Americans.

And why this analysis overestimates Youtube's and Adele's contribution to CO2 emissions

Most people are multi-tasking while listening to Adele (ie those 50 watts they are using are also going towards whatever else they do while listening to Adele, such as reaching for tissues to blot their tears), so you have to take a fraction of this number  🙂

Second, much of the power use in the US is now coming from natural gas, which is more efficient than coal, so you can cut down this number.

Third, tissues take a whole lot of energy to make. I'm betting that the raw number of tissues used while listening to Adele will increase the CO2 footprint.

How many times did you restart the song while reading this blog, BTW?

Thanks for reading!

- Jason Munster

Let Them Eat Grass - Free Range Livestock are Better For Environment

A friend and advisor, Chris Tuozzolo, more or less has a CSA for a free-range cow. He told me I should write a post, a rejoinder, actually, to my prior post on how beef causes nearly 10% of greenhouse gas emissions. A lot of people will think "free range cows must be better for the environment in every way, because they are natural!"

Shortest version: free range cows are better than feedlot cows by a factor of 2-3, putting them closer to pig-meat, but they still aren't amazing.

cows.

Other short version: the amount of disinformation on this topic is astounding. You literally can't find a reliable link on the first search page of google. All the articles are either by free market groups (feedlots are market efficient!), corn lobbyists (feedlots use our corn!), or vegans (there is no such thing as good meat to eat!). Much of the information that is available is "science" is in fake journals. In other words, it really is fake information put into journals that are made up to let any information through, provided you pay them to publish it. A reader literally needs an understanding of journal impact factor (ie, ratings of whether journals are real or BS, as it turns out some peer-reviewed journals will literally publish anything for a fee) to figure what's real and fake, and most people without PhDs don't know what impact factor means. In other words, I don't know how the rest of you can pick apart the real from the BS on this topic.

Full version

I did research. Holy crap, the bullshit (heh, punny) information is fed to you with a firehose on this one. This is a prime example of very smart people being paid to lie to you very effectively.

feedlot cows. Pic from EPA.

I'll keep the important information short. Grazing cattle are far better for the environment than feedlot cattle. The best information I can find (published in Science with over 2000 other authors having cited the article in follow-on research) (note, this article is on sustainable food and covers a lot more than meat, but it has a good chart on water use and GHG in varying feeding areas) says the following:

  • Grazing cattle produce half as much methane (a powerful greenhouse gas) per year as feedlot cattle
  • Grazing cattle take 1/5th the water per day
  • Pigs produce about the same GHGs in either setting, but keeping them clean in a feedlot takes 3x as much water
  • Grazing cattle take up to 33% longer to reach edible maturity (but they are leaner, so you get more actual meat). This came from other, less reliable sources, but we'll take it at face value
  • Adjusted for time to market*, feedlot cattle make 50% more GHGs and use 450% more water (looking at you, California, with the 4th most cattle of any state)
  • I think that time-to-market number may be made up, which would make the numbers more like 100% more GHG and 500% more water from feedlots

*That 33% more time to maturity also could be a manufactured number. I can't confirm it from reasonable sources. Even if it is true, then feedlot cows produce more pollution and take more to make.

Other problems with feedlots:

  • It is quite possible that constant antibiotic use in feedlots, constantly fed to animals as a means mean to prevent them from getting sick (increasing profits), leads to antibiotic resistance. So next time you get a case of untreatable gonorrhea from antibiotic resistance, raise a glass to industrial agro-farming (also known as American-style farming).
  • Grazing cows stand apart farther. Feedlot cows stand next to each other, helping spread of disease, so they need more antibiotics
  • Sustainable grazing (not often practiced in the US) promotes the change of deserts to land.
  • Once you start growing grass in desert areas, the grass holds the rainfall in place long enough so it absorbs into the ground rather than running off into rivers, making a positive feedback loop.

Seriously, watch this TED talk. It's starts with a powerful message. "To stop the spread of deserts, we killed a metric fuck-ton of elephants. Desertification still happened. It turns out we killed a bunch of innocent elephants. The way to reverse desertification is to have managed grazing." Don't watch it when drunk though, cause you'll either get very angry or very sad.

Hokay, so, we've now covered that managed grazing can actually reverse desertification, which means aquifers can start to take in more rainwater and some CO2 will be drawn down in the growth of new plants.

Why Vegans hate this

But yes, a subset of vegans (and likely a majority) love to argue that eating meat is an environmental disaster (it does push global warming happen faster), and so it upsets them that grazing cattle may actually be a positive net effect (counting the turning bare desert into growable land). Feedlot beef growth is definitely pretty bad, but it's highly likely that a well-managed grazing system for cattle will result in net positive benefits of environmental restoration.

You can't blame vegans too much for pushing that grazing is bad, because, as the rest of this article points out, it's hard to figure out which is correct data.

Journal Impact Factor and Judith Capper being a fake scientist

Journal impact factor is a measure of how important and useful certain journals are. Science and Nature have high impact factors. Also Proceedings of the National Academy of the Sciences (PNAS - pronounced P-nass, best/worst acronym ever), much more rigorous, has a high impact factor. The article I cite above is from Science, which means it was cited 2000 times. As in 2000 other journal articles reference and talk about it. It's kind of a big deal.

One counter article is by a "scientist" named Judith Capper. She publishes articles that say that feedlot farming is less GHG intensive than grazing. Except she published in a journal called Animals. It's literally a fake journal. It isn't listed as having impact factor. What's better, half of the 35 citing authors are her. She cites herself more than anyone else cites her. Pretty much, this is an udder bullshit article (haha) with awful science behind it. Typically when a majority of citations are yourself, it means everyone else thinks you're insane.

So you, dear reader, having never had to write a PhD thesis where you had to defend the sources you chose, would just see that this woman is a professor and has a PhD and say, "This must be true!" Except it's not. Articles do things like say, "Cows emit methane, and cows that eat grass take longer to bring to market, so more methane comes out!"

Except that cows that eat grass often emit less methane, cause there is less weird stuff in the grass (as the information earlier on in the article points out). So pretty much they take one true thing (cows produce methane) and then ignore the rest of the facts to lie about the ultimate maths.

I call BS.

In Closing

This post has been all over the place, and it over 1000 words. Pretty much, grazing cows are far better than feedlot cows for the environment. Grazing pigs just use less water, which is useful in California. Good luck finding real information on any of this, though.

Tesla's Powerwall - Not Economical

Tesla Powerwall

I'm gonna open by saying that I really like Tesla's powerpack. Technology isn't pushed past the bleeding edge without loss-leaders pioneering. That being said, the numbers, as usual, don't lie. On a per-unit-energy cost basis, these things aren't economic in most of the US. Once you consider the externalities, however, the overall benefit does make them "profitable." Likely you will see subsidies to internalize these externalities, thus making the powerpack work.

Unless the inverter costs too much. More on that later.

One major implication I haven't seen anyone talk about? Utility companies currently have to pay people with solar panels who produce excess electricity at market rates. They've been trying to get rid of this for years. This technology gives utilities every reason to demand they no longer pay people for their excess produced solar power. This has enormous implications. It's now indefensible to force utilities to buy at market rates the extra power produced by homes with solar. Read more near the bottom.

It's in my weight class!

Tesla's Powerwall next to a car. Small-ish and sleek. 7 inches deep, weighing 220 lbs

What is this Powerwall?

Powerwall is a power pack that you hang on your wall. It costs $3,000 for a 7kwh pack designed for a daily cycle, meaning it's charged and used once per day. This is the cost without installation. Also, this is the cost if you already have solar cells and an inverter. If you want to work with the grid alone, you have to buy an inverter*. Even if you already have solar cells and don't need an inverter, this seems like it's a product designed for the wealthy. Let's look at the math (my favorite part!)

*Inverters. Batteries and solar panels produce DC current, or Direct Current. This means it doesn't change phase. What we use in our homes is Alternating Current or AC. The alternating current means that the positive and negative terminals switch sides of the power plug. In the US, they switch sides 60 times per second. DC means that the terminals do not switch sides. Hence batteries having a + and - terminal, and all your non-battery electronics not having these.

The Maths!

We are going to make some of the rosiest assumptions in the world. First, though, let's get some solid data lines up. Take a peak at NPR's cost of electricity infos.

1. On average, people pay 12 cents per kwh of electricity

2. In Hawaii, they pay 33 cents. We'll use this as a case study.

3. The Northeast and California, two other case studies, pay about 16 cents.

4. The average American uses 900kwh of electricity per month in their home (from eia.gov).

Really rosy assumptions

1. The sun shines for 300 days a year and provides enough electricity to power your house during shining and to fully charge the battery

2. The electricity grid doesn't buy back your excess solar*. If they do have to buy it back, then the economics discussed here don't play out

3. You've already paid for all of your solar installation and you aren't concerned about those costs of that electricity going into this powerpack

4. These things don't degrade over time (extremely rosy assumption)

Hokay!

300 days per year of 7kwh of electricity provided by this beast is:

 300\frac{days}{yr} \cdot 7\frac{kwh}{day} \cdot = 2100 \frac{kwh}{yr}

So 2100 kwh/year. What's that get you in most of the US?

 \$ 0.12 \cdot 2100 = \$ 252

So $252 per year. For a $3000 battery pack. In most of the US, if your solar panels worked perfectly for 300 days a year, it'd take you 12 years to pay back your investment. This is a 6% annualized ROI (Return On Investment). In other words, you'd make more money in the stock market, so it's a bad investment, not even accounting for installation costs and with impractically rosy assumptions, in most of the US.

What about in the Northeast and California, where electricity is $0.16?

 \$ 0.16 \cdot 2100 =\$ 336

Or payback in 9 years. This is an 8% ROI, making it a decent investment.

Let's be realistic, though. In the Northeast, we have storms and winter. Solar panels don't work so great here. We aren't getting 300 cycles per year out of this. We'd be lucky to get 150, making it an 18 year payback, or about a 3% ROI. What about California? They actually might get 300 days of viable sun a year. So in California, you could be break-even.

Now what's the problem here? Normal people don't look for 8% ROI on their home upgrades. They look for 15%. Pretty much they want 3-5 year payback periods. So pretty much, someone has to have a very green outlook on life to buy one of these. Or there have to be subsidies (more later)

Hawaii

Hawaii has sunshine and electricity costs 33 cents. Let's say you've paid off your solar panels in Hawaii.

 \$ 0.33.2 \cdot 2100 =\$ 700

In Hawaii, with our rosy assumptions and no installation cost, the powerpack will pay for itself in 4.25 years, for a whopping 18% return on investment, without any subsidies. There is a viable business model here.

Seriously, someone go start a powerpack/solar panel installation company in Hawaii.

Anywhere else, and these things will need hefty subsidies.

Subsidies

Why would you subsidize these things? Easy. There are only two reliable power sources that can compensate for variability in solar power: hydro and natural gas. Every other power plant takes far too long to spin up to be useful. In other words, nuclear power doesn't stop producing pretty much ever. Coal power takes about a day to get to capacity, so it can't cycle well.
Hydro power is a limited resource. We are pretty much tapped out in the US, and what we have is already being used, so it can't ramp. We'd have to replace what's currently being used with coal, natural gas, or nuclear to use hydro for solar-grid reliability, so that entirely defeats the point.
Natural gas ramps quickly, and we have excess capacity in the US. Natural gas still produces CO2 that spreads globally, and NO2 that spreads locally. NO2 becomes a strong acid when you breath it in, so we have healthcare reasons to reduce it. Thus it might make sense to subsidize these powerpacks to make people more likely to buy them.
Second, this is good tech. It's pretty much where it needs to be in order to make sense to buy in many parts of the country, if you already have solar. Subsidizing it will cause further advancement in battery tech, making it that much more viable in a wider array of applications. Battery tech is one of the things holding us back from so many viable technology applications, so if there is something to subsidize that will more than pay for itself, it is battery tech that is nearly cost-even now.
Some Extra Thoughts on my Rosy Assumptions
*If Solar Companies don't need to buy back Electricity
In most places, if you produce excess electricity that you don't use, the solar company has to buy it back at market rates. So buying this powerpack and storing energy for commercial purposes is useless. All of the economic discussion above is bunk if the grid needs to buy your excess power. In other words, only greenies would buy it.
One important thing to consider. This product makes storing electricity from solar into a break-even cost in any sunny part of the country. Utilities have always hated paying for this. They lose money on it. They've fought legal battles to get it repealed. And now they have the ammunition they need to repeal it, because it's now no longer a burden to consumers to store their excess electricity for later use themselves.
Maybe consider buying utility stocks if you find a company that is over-exposed to paying for home-solar-produced power? I'd tell you to look towards California here.
Inverter Costs
If you don't have solar already, you have to pay for the inverter to make this thing convert DC back to AC for your home. I can't see any reason to do this. The cost differential between peak power and non-peak is about 4-6 cents in most places. Far too little to justify the expense of both an inverter and a powerpack. A gas generator is a better bet if you need reliable power.
Large Scale Efficacy
I'm betting the large-scale systems are more cost-effective. They don't need to be as small and as sleek. And you can have one large inverter for all of the daisy-chained power packs. Who would buy these? Commercial electricity buyers, like stores.
Who wouldn't buy these? Industrial complexes. They make deals directly with electricity companies and pay $0.07 to $0.10 per kwh.
Thanks for reading!
 - Jason Munster

Electricity Basics (and some advanced)

I received my second request for a post! This time the submitter asks for information about electricity, transmission, and how intermittent renewables like wind and solar fit in.

So, the first question:

1. Electricity, for the most part needs needs to be consumed the instant it is produced?

Yes. Storage of electricity can be done in batteries, or with pumped-water energy storage, but these are all just ways of being able to make electricity at some moment later in time. In short, electricity, once produced, is either used immediately or stored. Massive storage is not practical at the moment, so it's used.

2. Wind or Solar electricity is essentially in addition or parallel to the base load, and do little to lessen the use of coal, NG, or nuclear derived electricity!

This bring up an interesting point about electricity production. In the US, we have 60hz electricity. It's made 60hz by the generator design (in the US, Europe and other places use 50Hz power). Thermal power plants, those that burn things to produce power, rely on spinning a turbine in a magnetic field to produce power. The magnetic field is part of the turbine design, and is too complicated for this post to discuss in further detail. The turbine is spun because water, turned into steam by the heat from burning things or other reactions (coal, natural gas, or even heat from fission), expands rapidly from water to steam. It creates pressure, and then pushes through the turbines to spin them. The turbines spin at the exact rate they need to in order to produce 60hz electricity.

If we produce slightly too much electricity, the turbines start spinning slightly faster. To keep the grid at the right speed, electricity production is reduced at plants. If there is too little electricity, the turbines will slow down, and we'll fall below 60hz. There is a constant dance of the power plants and the electricity users to make everything balance. It's mostly automated, and happens very quickly.

What does this have to do with solar and wind? A lot. Solar and wind power output can be predicted, but not perfectly. If we want to maintain a perfect 60hz grid, we need to be able to adjust for wind and solar output. Because, again, electricity is used when it is made, and not stored. Coal and nuclear power plants aren't great at changing how much electricity they produce in a short timescale, so if we are going to have power plants to make the balance necessary, we need hydro and natural gas to account for the variability of the solar and wind. There isn't enough hydro to do that all over the country.

In  other words, if we want to maintain a 60hz grid, we are always going to have some amount of natural gas power plants.

But beyond that little wrinkle, solar and wind power absolutely offset coal-fired power plants. The more solar and wind we have, the less nuclear and fossil fuel power we need, in general.

In practice, do renewables offset much? See the chart below.

US primary energy consumption. Source: eia.gov info

Short version: Wind was about 1.2% of primary energy (primary energy counts burning oil for cars as well), and solar is 0.16%. So wind and solar can replace coal and nuclear, but it barely does currently.

Longer version: We can let the 60hz grid go from exactly 60hz to let it slide between 58 and 62. And then we can fairly easily do away with a lot of other power plants, as long as we have enough wind and solar. Note, however, that there aren't enough good wind sites in the US for this, and solar is currently too expensive and resource-demanding to replace fossil fuels.

3. Electricity is bought and sold just like a commodity?

In some ways, yes, but not exactly! There is a complicated daily bidding process, and several factors are brought into play.

This one is a bit confusing. I'll do my best. Power plants bid on the day-ahead market. They submit their bids to what is typically called an ISO, for Independent System Operator (some places call it differently, like RTO for Regional Transmission Organization. The ISO/RTO looks at the bids, looks at their best guess for power the next day, and then figures out how many of the power plants they need to hire for the day. Those that don't get hired don't actually burn anything or produce power. Those that do get hired, get hired at the rate of the highest bidder. Let's do an example to explain better.

Note that a MWh is one hour of one MW production. So a 600MW plant produces 600MWh in one our, and 1800MWh in 3 hours.

A plant says, "I can produce this many megawatts at this many dollars per megawatt." Power Plant 1 might say, "I can produce 600MW of coal power at $80/MWh." Power Plant 2, "I can produce 1000MW of natural gas power at $100/MWh." Power plant 3, a nuclear power plant, doesn't shut down. They just keep running. They say, "I can produce 1200MW at $0/MWh." Why? Cause they have to run anyways. They are delivering that power at any price. Power plant 4 is an old coal-fired power plant that has already paid for itself, so it's really cheap, and says, "I can provide 300MW at $50/MWh"

Let's assume it is determined that all of the less expensive power plants, along with Power Plant 2, need to run in order to satisfy electricity demand. They want $100/MWh. Power plant 1, despite bidding in at $80 per MWh, gets $100/MWh, nuclear plant 3 also gets $100/MWh, and coal plant 4 also gets $100/MWh.

On another day, it is determined that only enough electricity is needed for power plant 4 (and all the ones who bid below it). So Power plants 1 and 2 do not produce electricity, power plants 3 and 4 each get $50/MWh.

Should inputs become more expensive, then the power plant has to raise its price. Natural gas, for example, became a lot less expensive in the past 5 years. So they now produce electricity for less than a new coal fired power plant would. So they bid in for less.

A bit confusing, right? It gets more complicated than that. This is a great example to show that electricity is not exactly treated like a commodity.

Now what about solar and wind? Pretty much, if solar and wind is produced in the US, it is purchased, pretty much outside the normal bidding system. What happens to the bidding system if all power becomes solar and wind? There probably will still be some version of it, changed to fit the new system!

That's all for now, thanks for reading!

- Jason Munster

Remedying air pollution, one person at a time

One of my friends once told me, "If you are complaining about the government and aren't doing anything to solve the problem, then you are part of the problem."

I decided to do more than write about pollution associated with energy, and have started a side project to build a breathing filter (and mask that it will go with) for people living in and visiting countries with significant air pollution.

My apologies for not posting this sooner, I wanted to wait until I had finished a major milestone on my PhD that was taking literally all of my time. In other words, I didn't want to post about "working on" something that I had no time to work on. I hope to become active again in posting related articles now that I've a bit of free time again.

20,000 people die every day from air pollution. Most of them cannot afford current filters. It's time to change that.

So. China and India are not going to institute US-level air pollution controls on their power plants. So if they aren't going to filter the entire sky the way we do, the next best thing is to just filter the parts that people breath. By filtering it just before they breath

"But Jay," you say, "Aren't there other masks on the market already?"

Indeed, my friend, there are. Except most of them fail in one way or another. Nearly all of them fail to achieve a face-seal. This means that there are small leaks. Small leaks are fine when you are filtering large particles like water droplets (think viruses that travel on sneeze particles), because the leaks are often at 90 degree angles. The droplets can't make those 90 degree bends, and they get absorbed by the mask or deposited on the skin. This is why doctors masks can be fairly effective. PM2.5 and chemical pollutants, however, are small. PM2.5 is 1/30th the width of a human hair in diameter. It can easily make a 90 degree turn through a leak in a mask, and get into your lungs where it penetrates deeply, creates scar tissue, and then gives you asthma and lung cancer until it kills you. The other pollutants are literally molecules. They have no problem making any bend of any sort. If there is a leak, they are getting through.

Gas mask. The only true way to ensure there is no leak.

What's the easiest way to tell if your mask leaks? Take a deep, sharp breath. If your mask doesn't push against your face from suction until the pressure equilibrates, you don't have a good seal. So pretty much, every mask short of the one pictures above doesn't work.

So this is one part of what I will address. I've a few methods to ensure no leaks while maintaining low costs for masks. I'm not exactly going to be open on how I will do it, but this is happening.

So, if you plan on traveling in China, India, or near LA (heh) next year and need a breathing filter, be sure to talk to me.

- Jason Munster

Which Country has the Worst Air Pollution in the World?

Before I get into anything, this is a first in a series of three articles I am going to be releasing. Instead of my monthly release rate, I am going to be releasing them one each week. If you are traveling to or live in a polluted environment, I highly suggest you subscribe to the blog or do it as an RSS feed.

Now to the article!

If you guessed China, you guessed wrong. Did you get it wrong? If you say you didn't, I am going to call you a liar. Every person I know, when asked which country in the world has the worst air pollution, answered China. This includes experts on China, experts on air pollution, and experts on countries that are more polluted than china.

Also, the number of people that die per year from air pollution is staggering, more on that after the math.

China isn't even close to being the country with the most fouled air. That distinction belongs to India, by a huge margin.

Okay, well, let's delve further into it. Of the top 20 most polluted cities in the world, how many would you guess are in China? Okay, that was a trick question. China doesn't have any of the top 20 most polluted cities in the world. And India holds the distinction of having at least 10 of them.

A gate in India that can't be seen through air pollution.

Before getting to the science grit, one more important thing. Owing entirely to city air pollution in India, at least one study shows that Indian citizens living in cities have 30% less lung capacity than Europeans living in cities. So, pretty much, pollution makes it so

Okay, let's back up and discuss air pollution a bit.

What is Air Pollution? (This is the technical part of the post)

In this above mentioned study, air pollution is strictly PM2.5. Why is that? Because PM2.5 is particulates smaller than 2.5 microns, roughly 1/30th the width of human hair. They are small enough that they penetrate deep into the lungs, where they cause permanent damage and can lead to cancer. PM2.5 is produced by powerplants (mostly coal-fired) and any combustion-based motor vehicle. The EPA has a great guideline for PM2.5 if you want to read more.

There are other pollutants that everyone seems to ignore. Back in the day, you heard a lot about acid rain. Acid rain is caused by SO_2 and NO_2 . Combusting anything creates NO, cause there is so much N_2 in the air (78% of the stuff we breath is N_2 ) that some of it combines with oxygen during combustion, creating NO. NO reacts with O_2 to produce NO2 and O-, the latter of which produces ground-level ozone (more on that soon). Let's look at what happens to SO_2 and NO_2 in air:

2SO_2 + 2H_2O + O_2 \rightarrow 2H_2SO_4

So that's sulphuric acid.

2NO_2 + H_2O \rightarrow HNO_2 + HNO_3

And that is nitrous and nitric acid. Another fun reaction is:

NO + VOC + sunlight \rightarrow O_3

VOCs are Volatile Organic Carbons. It pretty much means organic matter in the air. It comes from plants. O_3 , or ozone, is bad for people and plants at ground level.

So let's review what happens here. Power plants burn fossil fuels, they produce PM2.5 which causes cancer, coal-fired powerplants produce SO_2 which becomes acid in your lungs, and all combustion plants produce NO_2 which also becomes acid in your lungs. PM2.5 is the worst, but the other pollutants are also bad. Burning coal causes the most of all of these pollutants. Lower grade coal, the stuff burned more often in China and India (the US has high grade coal), has less energy relative to pollutants, so it makes more pollution.

Now, exactly how bad are ozone, NOx ( NO_2 ) and SOx ( SO_2 )? They are all similar, so lets just look at SOx health effects according to the EPA. In short, exercising in an environment with this stuff is bad for you, and sends people to the emergency room. In the worst case scenario, it exacerbates or triggers asthma, heart attacks, and aneurysms, killing people nearly instantly. Long term exposure increases asthma and other health hazards. Now keep in mind that this stuff is considered less of a problem than PM2.5.

Back to the Qualitative

Okay, now that we know what the stuff is and what it does, let's get to some specific numbers. The World Health Organization indicates that air pollution is "single biggest environmental health risk in the world" the largest health hazard in the world, killing 7 million people per year.

What's the best way to deal with this stuff? Staying indoors helps a lot. Your house acts as a good barrier against it. Having a filter also helps. If you live in China or India, build one of these at your home. The filter will stop working eventually, so it will have replacement costs, but you can probably get clean air for around $100 per year for a single room in your house. Now keep in mind, this is a HEPA filter, which filters out only particles. Good luck with that SOx, NOx, and ozone. The guy who stapled together the filter and the fan states that it's the only thing you need for clean air in his blog. Clearly the PhD he is learning in psychology does not qualify him to know a lot about air quality. It doesn't disqualify him from knowing about it, but being completely unaware of the chemicals I described above does.

HEPA + fan. Good for PM2.5, useless vs. ozone, SOx, and NOx.

 

In other words, this filter will work inside, but you are still going to get bad chemicals living in your lungs. If you want to filter more, be prepared to shell out thousands of USD. Also, if you plan on going outside, or you want to exercise, if you work outside, you're pretty well screwed. There are a few masks that work, but all have their flaws or are expensive. More on this later, we've hit 1000 words and it's time to go.

Before we let me repeat one thing. If you are in a polluted area: Do. Not. Exercise. Anywhere. That. Isn't. Filtered. And no mask on the market filters out SOx, NOx, and Ozone.

Thanks for reading!

- Jason Munster

Solar Roadways: Full of Crap and Bad at Math

First of all, sorry it has been over a month since I've posted. I've decided to get together a few people to start addressing some of the things I write about, and that has taken my time up til now. I'll be posting once per month from here on out, on the first Sunday of every month. Today's post is a long one, but one of the most interesting I've written by far.

This is the one time where I will say the following: if you are short of time, skip directly to the math section. It shows a serious glaring deficiency of either forethought or disclosure on the part of the founders of Solar Roadways. Moreover, it shows they can't do basic math. Never trust an engineer who can't do basic math. It's a very crackpot idea.

Here We Go!

I've heard a lot of talk about Solar Roadways recently. I'm going to use it as an example of how to analyze some "science." After you follow the very basic math below, you will see that the team at Solar Roadways does not know what numbers to run*. A much larger problem: they suggest that solar roads can replace fossil fuel power, while simultaneously and surreptitiously admitting that they need a ton of grid power to make this work. So pretty much they are either dumb or straight up liars.

First, let's talk about why these roads might be good, from their point of view. Being a by-the-numbers type of guy, the first thing I did was check the "numbers" section of their website. While their assumptions are dubious at best (more on that later) They say that their roads could provide 3x the energy that the US needs, in kilowatt hours (kWh is a useless measurement here, cause it will be intermittent power. In other words, it produces no energy at night, and will need to be supplemented by fossil fuel power. More on that later). Also, the roads look a lot cooler, with light-up sections, and ability to melt snow so that road maintenance is reduced.

So the thing is wired to the grid so that if it snows, it can use heating elements to melt the snow instead of plowing it. But doesn't snow take a lot of energy to melt? Would it take less energy just to push it with a plow? Time for the math!

Math of Melting vs Pushing Snow

Plow trucks to be replaced by Solar Roads? Not happening.

Plow trucks to be replaced by Solar Roads? Not happening.

Okay. Let's assume middle-case scenario of 8 inches of snowfall, being removed with one sweep by plow trucks, and that this is between powder and heavy snow in consistency, which means 1" of water equivalent. A DOT snowplow clears 10' width of snow, or 120 inches. In one foot of movement forward and plowing 8" of snow it moves the water-weight of 1"x120"x12" or

 1 \cdot 120 \cdot 12 = 1440 in^3

Now we have to figure out how much energy cost this took in fuel, so we will later relate this to the mileage efficiency of a DOT truck. First, let's figure out how much energy it takes to melt this much snow into water. Do do this we need the latent heat of fusion, or the energy it takes to transition from ice to snow. It's 334 Joules/gram. How do we convert from cubic inches of water to grams? Easy. Because the metric system makes sense, one cm^3 of water = 1 gram. There are 2.54 cm per inch, so:

1440 in^3 * (2.54 cm/in)^3 = 23600g

Okay, we have grams, now let's calculate the energy to melt as much snow as a plow moves from driving 1':

23600 g \cdot 334 \frac{J}{g} = 7,880,000 J

Or ~7.8MJ. Per foot. Or, for a mile:

7.8 \frac{MJ}{ft} \cdot 5280 \frac{ft}{mile} = 41184MJ/mile to melt 8 inches of snow.

Okay, so, a plowtruck uses diesel. Each gallon of diesel has 136.6MJ. Very conservatively assuming a plowtruck gets ~5 miles to a gallon (I'm guessing it's more like 10, someone who has driven one, correct me and I will correct these #'s), it would take 27.3 MJ to plow one mile of snow. Compared to 41,184MJ to melt it. It literally takes 1500x as much energy to melt is as it would to move it.

This is what you would call a very very bad idea. Engineers as cofounders should know better than to let this slide as a potential solution.

End of Math Section

Okay, so now that we've completely dismantled the case of using these things to melt snow, lets move on to some other issues. We'll skip the minor issues, because that's just nitpicking, and move straight to the parts where they just don't know what they are talking about, and finish with things they clearly know about, but are purposefully misleading people with in order to get more money. Finally, we will close with me realizing that Nathan Fillion is a fool.

Okay, to the problems with this solar roadways project:

Dubious assumptions:

Things they don't understand: the supply lines of a very basic input.

REE mining in China is not a clean thing. Nor was it great in the US. Right now there is not enough world production to make enough of these solar roadway tiles. Look at this article to see more pictures of REE production in China.

They assume an 18.5% efficiency of the solar panels. These are panels that use Rare Earth Elements (REEs). On their FAQ, when someone asks if they are using REEs, they state (paraphrased), "Our electronics don't use silver or gold" (neither of which are REEs, so they are either changing the topic or don't know what question they are answering) "but we can use any solar cell." Good that they can use any solar cell, because there is not enough REE production in the world to produce solar at the scale they need to even replace one major highway with these. Bad they they use 18.5% as their assumed efficiency, because solar cells in this range of efficiency use REEs.

REEs are pretty much only produced in China, because producing them make a massive amount of pollution. Decades ago every other major country quit producing REEs because of the pollution they cause, and because China didn't care about pollution or health hazards, so the world was happy to let them pollute themselves and take their REEs. It's been so long since the US produced REEs that we literally don't know how. Solar Roadway's answer is "let's leave this to the government." They aren't addressing the problem at all. While other countries are looking to have their own production, it will take a very long time for this to come to fruition, and the production rate still won't be enough for a second-rate harvesting design (flat roads with bad optics vs. tilted panels with great optics to concentrate light perfectly).

At best, they can go with non-REE solar cells, which have about an 5-10% efficiency. That means that each of their hexagonal panels will produce half the power anticipated, and thus will make half as much money toward recuperating their costs. In other words, these non-REE solar panels need more basic raw materials (in terms of roadway) per kwh produced, and thus will cost more per unit energy, in an already material-intensive design for a solar cell. This shows that the project is lacking in any real expertise or understanding of the core problem they are trying to solve. Keep in mind that these are not dealbreakers. The team could hire an expert, or consulting, to fill in their knowledge gaps (likely the former, consultants are expensive, and they really need long-term help to bring this to fruition). Also, it doesn't negate all the other benefits of the solar roadways. Finally, non-REE solar panels are a hot topic in research. If the rest of the solar roadways tech is developed, and they are just waiting for good solar cells, it will rapidly enhance future deployment.

In short, the solar cells are a slight additional benefit to whatever holds them in this case of mass-distribution and inefficient use of cells. So if this new road itself doesn't compare favorably to asphalt, the project is sunk in the water.

Things they are just completely wrong/misleading about: melting snow, shutdown of fossil fuel, price of energy

We discussed the melting of snow. They suggest it replace snowplows. Bad idea. It's clearly not going to work, energetically speaking.

They keep talking about how 50% of US electricity use is from fossil fuels, and how these roads are going to replace it. This is so wrong that it is hard to debunk in one post. But here goes: First, only 40% of US primary energy (my link, please read it for background if you feel a bit lost, it is far briefer than this post) is for electricity. Second, only 66% electricity of this comes from fossil fuels. In other words, 26.4% of US electricity comes from fossil fuels (if we change all our transportation over to electric, these numbers will change, but that would require these roads to have induction power installed - AKA roads that provide the car with energy for driving so they don't have range issues). This is the total amount of emissions that could be replaced by solar roads in their current design.

Primary energy in the US. As detailed by the math above, only 25% of primary energy in the US can currently be replaced.

 

So, pretty much they are off to a bad/misleading start there. But this is nitpicking. The real issue comes in when they talk about replacing fossil fuels. First, they talk about heating the roads. This means they will have to put energy into the roads. Where will this energy come from? Power plants. So much for shutting down fossil fuel. But wait, there's more! Solar power is intermittent. It doesn't even work at night, so power plants also have to be on then. So pretty much, their idea of shutting down power plants is completely shot out of the water by these two things. Can solar roadways still be part of a larger energy solution? Well, not if they are heating roads to melt snow. That just takes far too much energy. If they scrap the melting snow idea and go to just producing energy? Yeah, it might help some. But let's get to one last funny part, the one that shows they know that they won't be shutting down fossil fuel power any time soon.

Energy storage. From their FAQ, they mention that there will be "virtual storage" in that during the day they will add power to the grid, and at night they will take power from the grid. This is double-speak to mean: during the day we will provide power that can offset coal and natural gas power plants. At night when we aren't producing, natural gas powerplants (again, my link) will fire up to power our roads (nuclear is not an option for power phasing like this, nuclear powerplants don't spin up or wind down on half-day timescales). In other words, they fully well understand that they aren't going to do away with the rest of the power grid, and that they aren't going to replace all those fossil fuel emissions. So pretty much, saying that these can replace our power grid is double-speak sales points.

The final problem? They don't understand energy distribution. Electricity is produced at about $0.03 to $0.08 per kwh at a power plant. By the time it arrives to us, we pay $0.13 to $0.25 (or $0.50 in Hawaii), because distribution costs a lot of money. Solar panels on our roofs produce power that costs about $0.15 to $0.20 cents per kwh, give or take. So the end-user cost of grid power is the same as that of house solar. But if you run that solar power through the distribution channels and add that price, suddenly you're talking $0.25 to $0.40 power. So, unless they are giving this power away for free, it's probably not gonna be a great solution.

Some Solutions

I've softened my usual tone quite a bit for this writeup, cause I don't want to be a complete naysayer of something who is trying to do something positive (sorry, I know how much you all know and love my biting sarcasm and scathing reviews).Outside of their false solution of trying to solve the energy/climate issue, this idea has some potential. On that note, rather than pointing out problems, I've come up with some great solutions.

My suggestions:

1: Nix the whole melting of snow concept to replace plow trucks. Energetically, it doesn't work. Plow trucks should still exist. Instead of replacing them, replace the salt and sand they need to spread. Make it so plowtrucks plow all but the last 1/8" of snow, then melt that (note, this is still a tremendous amount of energy, but stay with me). This will have a few benefits:

  • No more salt and sand on roads means less salt and sand damage to vehicles, making vehicles last longer
  • No more salt and sand on roads means that DOTs can save money buy not buying these things
  • ... no salt and sand runoff, which pollutes local waterways
  • ... animals that go to roadways in the spring to lick off accumulated salt won't do that, reducing traffic accidents from moose and deer, etc.

2: Get a bit more cognizant or REEs and their limitations. Don't use bad assumptions that are easy to poke holes in.

3: Stop selling people on false promises of doing away with fossil fuels. It makes the whole green movement look bad when prominent people are lying or severely misinformed.

4: Focus on the real potential of making these have inductive energy for electric cars. This could eliminate range anxiety (people fearing their electric cars will run out of energy and leave them stranded). Electric car sales will move a lot faster if people can drive from LA to SF, or between Boston/NYC/DC. The potential partnerships include every major car company that markets in the US. Also, this could reduce oil use, and drastically reduce air pollution from cars in these busy areas by further replacing combustion engines with electric ones (even if we power them with electricity from coal, a well-scrubbed coal plant produces fewer bad things than a car). Moreover, since people won't need fuel, they could be assessed a charge per mile driven instead. By whoever owns the roads. Here is your real money-maker for the roads, fellas. It will be far more lucrative than producing tiny amounts of electricity. Please get on this. It will lead to more electric car research, and more rapidly drive forward battery development, and it turns out that cars make a bunch of really bad pollution that causes harmful side effects like death.

This last bit, changing your startup's tack when a better model comes along, is important. And solar roadways needs to do that for a viable product, because their core solution faces a lot of headwinds (yay, sailing puns!) in break-even with their current model.

So, overall, these roads could be an excellent idea. The solar part, their main selling point, is BS because of cost, efficacy, and the need for gas-fired power plants to supplement them. The shutting down most fossil power plants is a lot of nonsense for the same reason. Making the environment better by reducing salt and sand use? Decent. Potentially by making most cars electric? Game-changer, but they are barely looking at that aspect right now. Probably cause they are too busy counting the piles of cash that indiegogo just threw at them (or, more likely, answering the insane number of emails that comes from this sort of campaign).

Hokay, that's my piece. Thanks for reading this long one.

- Jason Munster

Extra stuff!

Some background about Solar Roadways initial funding: They were funded by government SBIR. This stands for Small Business Innovative Research. It's for high-risk, high-reward research. In other words, this was considered high-risk from the start. They got a phase II, which means they did well. It's clear they still have issues and are still high-risk. But I'm glad someone is paying for research and innovation like this, especially because if it pays off, it could result in more jobs and more taxpayer base. That being said, they haven't received more funding or any grants to build this out further. Possibly cause it's a big, crazy idea. Elon Musk can pull off big, crazy ideas, because he is a brilliant manager and has a very strong personality. These guys are going to need some bigger guns on their team if they are going to make something of this project.

Second, Nathan Fillion is a bit of a fool. In touting Solar Roadways, he displays why pop culture heroes shouldn't get involved in matters outside their field of expertise (mainly, looking good in front of a camera, and pretending to be someone who they aren't in front of a camera). His adoration of something he doesn't understand falls deep within the territory of religious fervor. Nerds: just cause one of your heroes likes something doesn't mean it actually is plausible.

One final-final note: I know that this post is 3x longer than my rest. I assure you, it's far shorter than I wanted it to be. I don't believe in two-part posts very often, though. If you have read this far. please leave a comment so I can appreciate you forever 🙂

*Engineers who don't know what numbers to run are a bad investment. For my own company, all business types are skeptical of how much I know (or want to take advantage of me fully) until they find out that I used to be in finance and have a really good idea of the big picture of most things. In short, this company has a lot of potential once they take on broader experts.