The Tesla Battery (with Units!)

Friends and clients have been asking me questions about the Tesla Powerwall battery that has been getting so much press coverage lately. Can I power my house on one? Will it solve the renewable energy intermittency problem? Is it the game changer, the utility paradigm destroying techno-juggernaut that will usher in the renewable energy era?

No.

It is a good thing, though. What the Tesla folks have done is to package a Lithium Iron Phosphate (LiFPo) battery with a charger, battery management system, and cooling system in a tidy package. They are selling it wholesale at about $350 per kilowatt-hour, which is moderately cheaper than other LiFPo batteries on the market.

Let me stop right there with the term “kilowatt-hour” for a moment. It has been alternately amusing and profoundly frustrating to read news articles that interchangeably use “kilowatts,” “kilowatt-hours,” and the meaningless terms “kilowatts per day” and “watts-per-hour.” A brief tutorial follows. Energy professionals may go get a sandwich; I’ll be done in a few minutes.

Ok, we have AC, DC, amps, volts, watts, kilowatts, and kilowatt-hours (which is abbreviated kWh or kWhr). First, the garden hose analogy:

You’ve got a garden hose with a stream of water flowing out of it, filling a bucket. One factor is the rate of flow, or gallons per minute going through the hose. If you want to get right down to the miniature scale, it’s the number of water molecules per second that are passing a point in the hose. Another factor is the pressure pushing the water. The higher the pressure the more flow you get through a given hose. Then there is the bucket, filled with some volume of water.

Amps are like the flow. An amp is defined as some huge number of electrons passing a point in a wire in one second. Volts are like the pressure. Voltage is the force pushing the electrons through a wire. More voltage means more electrons per second in a given wire. One watt is one amp of flow being pushed by one volt of electrical pressure. Ten watts could be one amp pushed by ten volts or ten amps pushed by one volt, or any combination of amps and volts that multiply to equal ten. A kilowatt is one thousand watts (10 amps x 100 volts or 100 amps x 10 volts, or 20 amps at 50 volts, etc.). If you keep that thousand watts flowing for one hour you have delivered one kilowatt-hour. That’s like the water stored in the bucket, or the energy stored in the battery. Amps, volts, and watts are instantaneous measurements, units of power. Kilowatt-hours are created, delivered, stored, or used over time. They are units of energy.

For a more practical example, let’s say you have a toaster. You turn it over and look at the label, which says “115 Volts, 8.7 Amps.” By happy coincidence, these two numbers multiply to (almost exactly) 1,000 watts, or one kilowatt. Many of your closest friends come over for breakfast and they want toast. You keep the toaster going constantly for one hour. You have used one kilowatt-hour.

That toaster, however, uses AC (alternating current) electricity. Batteries and solar panels produce DC power, not AC. DC (direct current) electricity is like that water in the hose. All the electrons in the wire are continuously flowing in one direction, like those water molecules. With AC electricity those electrons are changing direction 60 times a second, back and forth. That’s because the voltage (electrical pressure) is changing direction 60 times per second. Remember that hum that came out of old fluorescent tube lights? That’s it.

To make AC out of DC you need a box full of electronics called an inverter. I’ll skip over the details here and just say “DC in, AC out.” Some inverters get their DC electricity from batteries, generally at 12, 24, or 48 volts. Others get their DC electricity directly from solar panels, generally at 250 to 500 volts.

Here is the first problem with the Tesla battery. It puts out DC electricity at 350 to 450 volts. There are only two inverter manufacturers, Fronius and Solar Edge, that have inverters that will take high voltage DC from batteries, and Solar Edge hasn’t released theirs on the market yet. That’s a serious limitation; the immature market for high voltage input battery-based inverters.

The second problem is capacity. There are two Tesla battery models, one with 7.5 kWh and one with 10 kWh. Your average American home uses over 20 kWh per day, so a single Tesla battery isn’t going to offer many hours of backup. They can be plugged together to make a larger battery bank, but the “power your home for $3,500” hype is just that.

The third problem is instantaneous power. A Tesla battery maxes out at 2,000 watts. That’s roughly equal to what you can get out of one standard wall outlet. If an air conditioner and a refrigerator come on at the same time the battery will shut itself down. Again, you can parallel multiple batteries, but you have to parallel multiple checkbooks to pay for this.

A more techie problem is that battery based inverters stay under 50 volts DC for a reason. The National Electrical Code gets a lot more stringent about wire and conduit, fuse protection and enclosures when battery banks go over 50 volts. The added safeguards add expense.

On the subject of expense, after paying $3,500 for a Tesla battery you will have to pay that again for an inverter, electrical hardware and an electrician to make it work. That is, if you can find anyone willing and trained to work with a 350 volt battery bank.

My verdict is: A missed opportunity. The battery needs more integration into a product that delivers AC power. Tesla could have partnered with Fronius or Solar Edge to build the inverter and AC interface into that sleek box. Then any electrician could easily hang the unit on the wall and connect it into a household electrical system. With all the capital and engineering prowess at its disposal I am mystified as to why Tesla didn’t.

I guess the energy revolution has been delayed.

(Elon Musk, if you are reading this, I am willing to consult on product design for any old floor model electric roadster you happen to have sitting around.)

A Throwaway Line

Treason doth never prosper:  what ’s the reason?

Why, if it prosper, none dare call it treason.

Sir John Harrington

Prosperum ac felix scelus

Virtus vocatur

(Successful and fortunate crime is called virtue)

Seneca

I just read an interview with Abol Hassan Bani-Sadr, the first president of the Islamic Republic of Iran. Those of you over a certain age might remember him from the time of the Iranian hostage crisis in 1980; a thin man with large glasses and a trim moustache, the non-clerical face of revolutionary Iran.

Bani-Sadr is living in exile in France, as he has since 1982. He was a strong advocate of democracy and human rights, which put him at odds with the mullahs running Iran at that time. He and his family had to flee for their lives.

The interview is about the nuclear deal between Iran and the western powers, led by the U.S. In Bani -Sadr’s opinion, the deal is essentially a capitulation by Iran on all major points, which the mullahs have covered up by mistranslating the main points of the agreement into Persian for their government controlled news media. Apparently the Iranians are celebrating a better deal than they actually got.

That’s fine, but for me it is only one of the significant parts of the interview.  While making a point about the poor judgement of the mullahs he speaks of two previous failures. One is their insistence in prolonging the Iran-Iraq war after they had gained the upper hand. The other is the 1980 hostage crisis, when Iranian students, encouraged by elements of the government, stormed the U.S. embassy and took the staff hostage. The significant section:

“In a longer-term sense, the Lausanne agreement no doubt adds to the sense among ordinary Iranians that, yet again, the regime has put the country in such a dangerous position. For the third time since the 1979 revolution, the regime has prolonged a political crisis to the point of defeat. The first, of which I had first hand knowledge, was the dangerous game played during the occupation of the American embassy in Tehran, the release of the hostages and the “October surprise” that bolstered Ronald Reagan’s election as U.S. president. The second was during the Iran–Iraq war, when the regime failed to end the war at a point of strength in 1981 and 1982 and instead ended it in defeat in 1988.” (Emphasis mine)

Here Bani-Sadr repeats what he wrote in his autobiography, My Turn to Speak, which focused on his political career. A portion of the book covers the covert deal struck between Iran and high level representatives of the Republican Party. The Republican negotiators were none other than George H. W. Bush, later Vice President under Reagan and then President himself, and William Casey, later head of the CIA. Bush and Casey offered a covertly friendly relationship with a Republican administration in the White House, including military support, if the Iranians kept the hostages in Iran till after the 1980 election. As it turned out, this offer became the Iran-Contra scandal, with the Reagan Administration covertly selling anti-aircraft missiles to Iran and using the proceeds to illegally support the Contras in Nicaragua.

Bani-Sadr is not alone in pointing the finger at the Republicans. Yassir Arafat and Bassam Abu Sharif of the Palestine Liberation Organization also acknowledged being approached on this subject by a Reagan associate, John Shaheen. Shaheen told Sharif and Arafat that he wanted the PLO to act as a go-between with the Iranians to keep the hostages from being released.  The quid pro quo was recognition by the Reagan administration. Arafat declined to participate, but found out that Shaheen, Casey, and Bush had found back channels directly to the Iranians. Many years later Arafat told ex-president Carter about the treasonous dealings that had gone on behind his back.

In a federal court hearing in 1988 (U.S. vs. Rupp, Docket 88-CR-112) the issue at hand was bank fraud by a pilot and former CIA agent named Heinrich Rupp. Rupp testified that he had flown Bush and Casey to France in October 1980 for secret negotiations with the Iranians over the hostage crisis. Another witness in the case, an arms merchant named Richard Brenneke, testified that he was present at a meeting between Casey and Cyrus Hashemi, a representative of Ali Akbar Rafsanjani, a mullah in the Iranian governing council. Hashemi was later involved in the dealings known as Irangate. The initial offer was that the U.S. would deliver $40 million to French intermediaries, who would then purchase arms and transfer them to Iran.

Of course, the negotiations between the Carter Administration and the Iranians stalled in late October, and Carter couldn’t overcome the hostage handicap.

For Bani-Sadr it was just an aside, an example to make a point about a pressing contemporary issue. For me it is reopening an old wound. The election of Ronald Reagan was based on an act of gross treason by Bush and Casey (among others), who ended up at the highest levels of the U.S. government. That act begat more treason in the secret government-within-a-government that ran the Iran-Contra operation. Our government continued down a road of foreign intervention that brought us to Iraq, Afghanistan, and the present maelstrom in the Middle East.

As the writer and former military officer Andrew Bacevich pointed out in his book The Limits of Power, we faced a decision point in 1980. We could follow the path of intervention in the Middle East and imperial dominance in general; business as usual, headed down a dead end street. Conversely, we could have gone down the path of energy efficiency, renewable energy, and a foreign policy that acknowledged the interests of ordinary people in other countries. There are reports that people in military and intelligence circles were horrified by President Carter’s ideas for a foreign policy based on human rights and ethics. His famous speech, dubbed the “Malaise Speech” by hostile politicos, didn’t use the word “malaise,” but offered a vision of a more democratic, cooperative, and energy independent nation. It must have been a terrifying prospect for the oil companies and military contractors, along with big business interests in general.

Here’s a key sentence: “Point one: I am tonight setting a clear goal for the energy policy of the United States. Beginning this moment, this Nation will never use more foreign oil than we did in 1977—never. From now on, every new addition to our demand for energy will be met from our own production and our own conservation.”

You should read it and, perhaps, weep for what might have been.

Richard, the Third Cubicle on the Left

It's April 1st. The temperature dropped to 15F last night and it is supposed to drop to 17F tonight. Snow and ice pellets are in the forecast for the next week. This is some kind of cosmic joke. In that spirit, and with all due apologies to William Shakespeare ("Spinning Billy" as he will now be known) I present the following vignette.

Richard, the Third Cubicle on the Left

(A Winter's Tale)

Act 1

Scene 1: A cluttered cubicle. RICHARD hunches over a computer keyboard

RICHARD:

Now is the winter of our discontent

Stretched into summer by this sunless murk;

And all the clouds that lour'd upon our house

Have dumped their snow and left us buried.

Now are our brows bound with luxurious fleece,

Our itching arms gummed up with emollients,

Our December snows changed to April sleeting,

Our dreadful March with sub-zero weather.

Grim-visaged winter has stalled his polar front,

And now, while mounting fuel bills

Blight the souls of fearful homeowners,

He labors grimly 'gainst your windshield scraper

To the distant rumbling of a plow.

But I, that am not shaped for winter sports

Nor made to ski like a glamorous looking ass;

I, that am rudely stamped, and lack dexterity

To shred before wandering back to the lift;

I, that am curtailed of fair vacation,

Cheated of beach time by dissembling HR,

Breakfast unfinished, sent before my time

Into this freezing world, scarce half wrapped up,

And that so lame and unfashionable,

That teens snark at me as I halt by them—

Why I, with weak pipes about to freeze,

Have no delight to pass away the time,

Unless to see my shadow in the sunlamp

And descant upon the cold enormity.

And therefore, since I cannot prove a loafer

To entertain myself upon southern fairways,

I am determined to prove a slacker

And use up all my sick days.

Plots have I laid, inductions dangerous,

By drunken office parties, emails, and tweets,

To set my supervisor and HR

In deadly hate the one against the other;

And if HR be as skewed and unjust,

As I am subtle, false, and treacherous,

This day should the schedule be totally screwed up

About a BCC which says that we

from HR's errors have an extra FTE.

Dive, thoughts, down to my soul—here Lumbergh comes.

If you are curious, here is the original text.

Oh, and if you are unfamiliar with Lumburgh, here he is.

ISIS and Adultery

We’ve all been watching the conflict in Syria and Iraq involving a group called ISIS, or ISIL, or IS, the Islamic State. They are a group of literalist fundamentalist Muslims. According to a recent article in The Atlantic, literally literalist, as in every exact word in the Koran interpreted as if we were living in the 8^th century. They emerged out of the centuries old Sunni-Shia conflict combined with Saudi financing and the anarchic power vacuum created by Western intervention. Iraq went from being governed by an oppressive Sunni minority to a vengeful Shia majority, while the Alawite Shia government in Syria got weakened by a Sunni rebellion. Chaos plus revenge plus opportunity plus absolutist religious schism equals bad craziness.

My guess is that eventually even the backers of ISIS will realize that the movement has outlived its usefulness. A slowly growing consensus among Arab states is emerging, that they need to engage in some collective action. And ISIS will find, as we did, that conquering Iraq and governing it are two different things.

In the meantime, a lot of pixels have been dedicated to the debate over the religious justifications of ISIS, the inherent violence in Islam (or not), and who determines the proper interpretation of a religion.

I’d like to point out that it is a damned good thing that we don’t have any literal Christian literalists in the U.S. Sure, we have people who claim to be biblical literalists, but they ignore great swathes of Deuteronomy and Leviticus that would get them punted into a secure psychiatric facility. Give those two books a read sometime and imagine some suburban megachurch-goers burning entrails on the front steps of their drive-in cathedral or sprinkling blood (seven times with the right forefinger, facing east) on the altar. It would add an edge to those “gospel of prosperity” sermons, but would probably get them a psychiatric evaluation as well. Read “The Year of Living Biblically” for a funny take on trying to be a literal literalist.

The table manners of the Old Testament are one thing, but then there’s the smiting. From just a cursory reading a literal-literalist would find it necessary to kill:

Blasphemers

Sabbath Breakers

Disobedient Children

Teachers of a foreign religion

Apostates

Adulterers

I mean, Moses had his people stone a guy to death for picking up sticks on the Sabbath. Picking up sticks? It doesn’t bode well for millions of convenience store clerks, restaurant employees, and factory shift workers.

For the moment I’d like to focus on the last one, adultery. The lowest numbers I can find in national polls are a 14% infidelity rate for married women and 22% for married men. Given about 120 million married people in the U.S. that works out to 10.8 million adulterers. Talk about an epic slaughter. It got me thinking about the logistics.

Let’s say it takes about 100 fist sized rocks to properly stone one of these sinners to death. I might be understating the case, but it’s a round number. That’s about 1.5 cubic feet of stone, so to do the whole job properly would take about 600,000 cubic yards of stone. That’s 60,000 10-yard dump trucks. Owners of heavy equipment and gravel pits would be way into Christian literalism. You might say, “People could just pick up stones off the ground,” but try to find 100 fist sized stones in one place in Manhattan or L.A. Or the sandy regions of Georgia, for that matter. I suppose people could wash the stones off and reuse them, but 1) ew, and 2) it would really slow down the process.

It would be labor intensive as well. 10.8 million stonings would overwork even the most ardent Christians. If you are a literal-literalist Christian, be prepared to spend your evenings with your pitching elbow in a bucket of ice. Stock up on Ibuprofen. You’ll end up with bone spurs, eroded cartilage and probably a torn rotator cuff.  I could see “Stoner’s Elbow” becoming a thing. But hey, Ad Majorem Dei Gloriam, right?

Of course, if a group of Christians went literally literalist on us I can imagine a coalition of blasphemers, adulterers, Sabbath-workers and other-religionists (including non-literalists) organizing to oppose them. “Everybody Must Get Stoned” is kind of funny when Dylan sings it, but not when actual rocks start to fly.

It would be like present day Syria and Iraq. Except Christian. This is one of the few instances when I am perfectly happy about hypocrisy.

The End Run

I want to bring a piece of information to you. In an article published today by The Intercept, Jeremy Scahill and Josh Begley reveal that British and US intelligence agencies hacked into the computer systems of the world’s largest manufacturer of SIM cards, allowing them to steal millions of encryption keys at will. Here’s the link to the article.

 A brief explanation: Your mobile phone or wireless enabled tablet is essentially part radio. It communicates with the nearest cell tower using a radio signal. Therein lies a problem of privacy. Your phone and the cell tower are both broadcasting a radio signal in all directions. What if someone is listening in?

In your phone there is a small chip, about the size of a thumbnail, containing information. This subscriber identification module, or SIM, contains a code that encrypts all your phone calls and texts so that if someone intercepts the signal all they will get is a string of gibberish. Modern 3G and 4G encryption is actually rather good. So good, in fact, that GCHQ (Government Communications Headquarters, the British version of our NSA) and the NSA have trouble breaking it. Rather than breaking it, back in 2009 they decided to do an end run around it.

They hacked into the computer systems of Gemalto, the aforementioned SIM card manufacturer, and cyber-stalked its employees. (Gemalto supplies AT&T, Verizon, T-Mobile, and Sprint, along with 450 others) They figured out how to automate the theft of the codes burned into millions of SIM cards distributed worldwide. They also figured out how to associate these codes with individuals who own mobile phones.

What this means is that any time they want, the NSA and GCHQ can easily decrypt phone calls and text messages from any Gemalto-SIM phone. It is a massive, ongoing, and deliberate breach of privacy. I’ll be interested to see the reaction to this when it becomes generally known.

In the meantime, the Electronic Frontier Foundation recommends the use of apps such as Signal/Redphone (iOS/Android versions), Silent Phone, and Silent Text to encrypt your communications, if you feel the need.

Am I the only one who thinks that the NSA needs a top-to-bottom ream and steam to clean the place out?