Economics of Energy Storage

There is a lot being written about energy storage.  Much of this is in the context of managing renewable energy intermittency.  A metric called Energy Stored On electrical energy Invested (ESOI) has been developed.  Among other things it is used to address the decision whether to curtail energy or store and use.  I found this summary to be helpful.  There are a variety of other options to avoid curtailment.  Two in particular are expanding the transmission grid.  This has two additional benefits.  First it improves reliability by creating additional redundant paths for electricity in the event of a localized outage.  The second is to harden relative to terrorist attack.  Currently there are 9 substations which if taken out at the same time could shut down the US grid for months.  Expanding the transmission network would add redundancy making it a much less attractive target for terrorists.

Lithium Ion, Batteries

Posted in Uncategorized | Leave a comment

Electric Vehicles Are Great Match to Wind in Many Areas

EVs charge mostly at night.  In fact they can be set on a timer to charge after midnight when rates are cheaper.  In many areas this provides an excellent match to wind power.  During the high demand summer months, California offers a great example of this with wind picking up as the sun goes down.

CAISO close up of hourly renewable production 3013 08 15Consider Texas, the most wind rich state in the country.  They are building out wind rapidly.  However perhaps not as much as they would like.  The problem is that wind in Texas is night peaking but the load from air conditioning peaks in the daytime.  Wind is not a good match to the Texas load as it stands.  But if EVs were ubiquitous they could charge at night enabling Texas to better take advantage of their wind resource while reducing carbon emissions from autos and from the coal and natural gas power plants that would otherwise be required to charge them.

The graphs below are typical of summer load and generation profiles in Texas and illustrates the point well.

Ercot wind 7-25-2013While the graphs above show the resource for a day, the graph below shows the behavior for the entire year.

Trent Mesa average hourly wind profilesThe subscription based educational portal Solar Learning Lab provides access to a variety of solar data sites from around the country.  The screenshot below shows data from an Archer City Texas solar array.  The match with wind above is quite good.  If Texas pursues solar to augment wind they will have an excellent complementary resource. 

Solar Archer City power 8-29-2014Solar resource in Archer City Texas.

It is important to note that the fit is not perfect.  Around 7:00pm, solar has dropped off considerably while wind has not yet ramped.  This can be addressed by use of tracking arrays.  In the Southwest they tend to be cost effective on an energy basis and in this case would have the added benefit of making the solar / wind pairing eligible for a much higher capacity credit.  In other words, the tracking arrays would reduce or possibly eliminate the reliance on peakers for the 1/2 hour transition from solar to wind.  Also, due to the very short transition period, this could also be addressed with demand side management.  The technology for utility control of load such as hot water heaters and air conditioners is mature.  Businesses could save by reducing AC from 6:30pm to 8:00pm and homes could similarly reduce air conditioning in a tighter band to address this as well. 

In the graphs below, a fixed and tracking array are compared.  These two solar arrays are at Rensselaer Polytechnic Institute.  They are the same size and use the same inverters.  One is on a fixed mount and the other on a tracking mount.  Late in the day there is harvest of electricity during the transition period which otherwise would be underserved by renewable resources.  This is high value and further justifies the expenditure for electricity.

Fixed Tracking Compared 8-24-2013Graph showing improved ability of the PV array to match load as it ramps to peak in the late afternoon.

Similar profiles are observed in California.  While it is true that the wind resource in late fall and winter is low in California, so to is their load.  In the summer when there is the highest demand on the grid, wind power is very reliable and available through the night.  In fact, if you look at the data, it turns out that wind power is very predictable in California.

The term intermittent can mean many things.  The general understanding is that intermittent means unpredictable or random.  However, the term is often applied even in the case of predictable renewable resources such as wind in TX or solar in the Southwest.  In each case, suggesting that the resource is random is naive at best.  See graph below of solar production from a CA based solar array.  Even on the rainy day the array produces considerable energy.  Of course on a rainy day, temps and therefore AC demand would be lower.  Generally , clouds and rain are predictable in CA.  The combination of advanced notice and load reduction minimize and possibly eliminate the grid stability ramifications that may be existent for high penetration of solar in other areas.

Solar Energy Production - Museum of Water and Life, Hemet CA

Energy production from a 600kW solar array in Hemet CA. Energy production is consistent and predictable.

Posted in EV PEV, New Energy Paradigm, Path to a New Paradigm, Resources and Information | Tagged , , , , , , , , , , | Leave a comment

Li_Ion at $270 / kWhr EV Tipping Point May Be Closer Than The Analysts Think

Li_Ion at $270 / kWhr EV Tipping Point May Be Closer Than The Analysts Think.

via Li_Ion at $270 / kWhr EV Tipping Point May Be Closer Than The Analysts Think.

Posted in EV PEV, New Energy Paradigm, Storage | Tagged , | Leave a comment

Tesla is the Most Important Car Company – Morgan Stanley

Tesla is the Most Important Car Company – Morgan Stanley.

via Tesla is the Most Important Car Company – Morgan Stanley.

Posted in New Energy Paradigm | Tagged , , , | Leave a comment

Growth of Windpower in Fascinating Interactive Graphic

Click Here: Note there may be a pop-up blocking. There is an X at the upper right of the pop-up that you can click on to make it go away.

Posted in New Energy Paradigm | Tagged , , , | Leave a comment

Tesla The Company

This post is a catchall to collect top stories and information about Tesla and Elon Musk.  I will post links to interesting information and to capture links that I don’t have time to write about at the time I spot them.

Li ion vs pumped hydro

Giga Factory and rapidly declining price of Lithium Ion Storage:

Giga Factory will be up and running by late 2016 and expect more of them by 2020.  See more on this here.

Giga factory updates, maybe Reno.

Comparing lithium Ion at 2013 prices to pumped storage.

These are blog posts by a guy who saw Elon Musk taking to the California PUC.  He provided his notes on key points.  In the first of these posts the take-away is that Li-ion materials cost about $65 / kWhr setting a near term limit on costs (materials prices can drop if demand justifies developing processes for synthesizing or obtaining them for less cost).

In the second post he suggests that oil is much better used as a raw material for synthetics and plastics.  I also found it interesting that he thought both SpaceX and Tesla were going to fail.  I have always thought the positive thinkers take it too far when they suggest that you should divorce yourself from reality.  Here he is, the most significant entrepreneur of our time acknowledging that it is all about hard work and drive, not denial of reality, that wins the day.

Peter Rive – Don’t cut the cord.  Storage is good, the grid is good, the network effect adds value – stay grid connected.

This is just the beginning – Expect Tesla to grow their battery business very rapidly.

More on the gigafactory and its implications for the future.

Direct Sales Model

This is a good article about resistance to Tesla’s direct sales model.  Dealers are trying to prevent Tesla from selling direct to the customer.  This strikes me as anti-competitive.  Here is an article about another car company that wants to use a similar sales model and may be an ally for Tesla.

Posted in dangers of the old paradigm, EV PEV, Exciting Technology Breakthroughs, Fossil Fuel Depletion, New Energy Paradigm, Path to a New Paradigm, Storage | Tagged , , , , , , | Leave a comment

Real World Impact of Climate Change Revisited

Hoover Dam with intakes

In 2012 I visited Lake Meade and Hoover Dam and I was immediately struck by the white line around the lake.  It looks like it is painted on but it is actually a mineral deposit that shows where the water has been in the past.  People now refer to it as the bathtub ring.  Things were so bad, I really thought that natural cycles would cause it to resolve itself by now but it has not.  The drought relentlessly continues.  The lake is now down to roughly 40%, by volume, of its maximum capacity.  Since the water level is low, the head for the generators is less.  This substantially diminishes the electrical generation from the dam.  In 2012 wrote a blog post about it here.  Las Vegas is so concerned that they are building a new tunnel to provide access to the water deeper down, their current tunnel intake may soon be above the water line and unable to sip water from the lake.


This New York Times article does a nice job of communicating the magnitude of the problem.  For the first time they are reducing flow from Lake Powell.  With the water already at record low levels this promises to make water politics out West get pretty interesting.  In the NYT article they mention that the 20th century was a relatively wet century as far as the Colorado is concerned.  So even without climate change the scenario unfolding is not as surprising as the public has been led to believe.  But add climate change to the lower typical flow and we are looking at a challenging scenario for the 21st century.

Lake Meade July 2014

“If Lake Mead goes below elevation 1,000” — 1,000 feet above sea level — “we lose any capacity to pump water to serve the municipal needs of seven in 10 people in the state of Nevada,”

The Bathtub Ring

The Bathtub Ring – Click Image To Enlarge


Hoover Intakes

Intake Towers. Look at the people at the top of the dam for perspective.

Posted in Climate Change, dangers of the old paradigm | Tagged , , | Leave a comment

Time of Use Metering


Factsheet_Smart_Grid_Dynamic_Pricing is a nice overview of time of use metering designed to be consumer friendly.

Posted in New Energy Paradigm, Path to a New Paradigm | Tagged , , | Leave a comment

Li_Ion at $270 / kWhr EV Tipping Point May Be Closer Than The Analysts Think

Nissan has just announced that they will provide replacement batteries for their Leaf cars for $6500 = $5500 after trade-in for your old battery pack.  This puts Li-Ion battery packsat about $270 / kWhr.  That is well within the range where analysts expect EVs to break out and go mainstream.  At this time this is a leading indicator, it is very encouraging.

Li-Ion battery Improvement Curve

Cost per kWhr = $6500 / 24 kWhr = $270

This adds credibility to a number of recent studies and prognostications suggesting that Li-Ion battery prices will drop rapidly to $200 / kWhr or less by 2020.  The rapid drop in automotive Li-ion battery prices will flatten as they become comparable to consumer electronics Li-ion batteries.  However the EV market will continue to ramp volume and drive down the cost of Li-Ion along the consumer battery experience curve, or close to it.

While the current Leaf replacement price is a money loser for the company, they also are on record saying that there have been no takers.  In other words, the batteries are holding up quite well.  No doubt they knew this and priced it for profitability when a large number of the batteries do degrade to the point of needing replacement, probably in the 1 – 3 year time frame.  In other words they are willing to take small losses at the beginning of the replacement program in order to provide peace of mind for Leaf customers and drive sales.

Kuhlman explains that Nissan is subsidizing the replacement packs as “a ‘customer-first’ initiative” after much discussion of the need for a transparent replacement price–which the company “hear loud and clear from [Leaf] owners and lessors.”

All that said, however, after the first month, “we have yet to sell one battery as part of the program.”

Since the studies mentioned above Tesla has announced their plans for a Giga factory which will double world production from 2013 levels.  Recently, Elon Musk was quoted  saying “We’re probably going to do two or maybe three states all the way to creating a foundation and completing the plans and getting approvals and everything”.  It does not take a clarivoiant to read the tea leaves and deduce that Tesla is positioning themselves to open multiple giga factories by 2020.  Not only does this suggest that EV’s will reach the tipping point before 2020, it also has pleasant ramifications for laptop price / performance since the same Li-ion improvements can pass through to that and many other applications.


Leaf, Tesla, Electric Vehicle, lithium ion, cost reduction, HEV, PHEV, EV, Elon Musk, Nissan

Posted in EV PEV, New Energy Paradigm, Path to a New Paradigm, Storage | Tagged , , , , , , , , , , , | 4 Comments

What Percentage of the Worlds Land Area Would Be Required to Run Everything With Solar?

World Solar Map

I calculated the land needed if the world were going to use 100% solar energy for electricity and for electric cars.  The total land required is less than 0.3%.  That is roughly the size of Arizona.  That sounds huge initially but to put it in perspective, the area of the US covered by roads and parking lots is 61,000 square miles which is about 1/4 of the area required.  There is also a lot of rooftop space available.  Since wind will also likely be used and there is a lot of wind power available, it is likely that about 1/4 would be powered by solar and that could be primarily on existing built space such as roofs parking lots and possibly roads and bridges.

This calculation is for all electricity for 10 billion people having the same energy intensity as in the US.  It also assumes that everyone drives as far as US drivers and uses electric vehicles.  This accounts for about 2/3 of and industrialized world’s energy use.

Non electrical loads such as oil refining and chemical processes and heating buildings can benefit significantly by known efficiency measures.  This is calculated on an energy basis an assumes that there is a way to store the electricity generated during the day for night time use.  It is a sanity check.  If there wasn’t enough land then we wouldn’t need to talk about energy storage.  But the numbers show that there is plenty of land.

Posted in Path to a New Paradigm | Tagged , , , , , | Leave a comment