Thursday, August 27, 2015

Eight Months With The BMW i8....Amazing!

First a disclaimer, I realize that having two BMW BEV i3's as daily drivers and a BMW i8 as an evening, weekend and trip car is a very fortunate position to be in life,  I am extremely grateful.

The BMW i8 is our road tripping car

Our BMW i8 is now 8 months old and has 7200 miles on the odometer.  4200 of those miles involved three long road trips, one of the trips was 1900 miles in total distance, driving the i8 through four states in five days. On each of these trips we had no chance to charge and the trips were made entirely on gasoline. We averaged 32 mpg on these trips.

As I've said many times before, when we were a two EV family with no range extender or gas car for the prior three years,  we would borrow  or rent a BMW 3 series car for our long road trips, those cars averaged around 28 mpg.  The overall point is that even when I possessed the EV Purity card, I still used gasoline occasionally.

We have put about 3200 local miles on the BMW i8 during the past 8 months.  I suspect this amount will go down a bit in the coming years as we try to keep the miles on this beautiful car low. My guess is that between road tripping and local miles we will average about 7000 miles a year over the first four or five years.

My driving style is sporting, loving the twisties, with each trip in the car involving at least one or two leftward ticks of the stick over to sport mode for a 0-60 sprint, an onramp dash or fun on the twisties, that's all it takes to put a huge smile on my face.

The BMW i8 remains a 3300lb rare earth magnet, pulling attention from anyone who sees the car.  A typical 20 mile trip in the car involves a few dozen i-phone shots from surrounding cars,  a conversation with folks as we get out of the car or into the car, and occasionally if the mood is right and I have the time, a "Can I sit in your car"  moment where I become the photographer of an unknown person sitting in my car.   Occasionally a BMW enthusiast will see the car walk over to us very excitedly and proceed to tell me everything about my car, these events can easily interrupt a dinner and take 30 minutes or so.   We've had folks go up to the restaurant host and ask who owns the car, then walk right down to our table and ask for the keys so they can look inside.  Julie and I take turns when this happens escorting the persons to the car and opening the doors for them.

I'm hoping this attention dies down a little bit, and I suspect it will, but at least for this first year it has been pretty intense for my wife and I.  It can both be fun and a drawback depending on the situation, but we try to be good ambassadors realizing how fortunate we are.

Our trips in the i8 seem to break down into four distinct categories:

Long road trips in the BMW i8, 32 mpg.
Local trips under 18 miles,  to dinner and sights around our city, all electric.
Regional trips under 40 miles to sights around the area, 70mpg.
Longer regional trips around So-Cal, 50mpg.

We have a dual head charger  in our garage, so after each trip we plug the BMW i8 into the level 2 charger.

Combined we are averaging 56 mpg with this almost 500 mile screen grab showing 58mpg.  Most cars in this competitive class driven in the same manor that I drive the BMW i8 would return well below 20 mpg representing an astonishing tripling of efficiency.

The BMW i8 provides a forward looking glimpse into the future of all the BMW lines as BMW transitions to variants of this drivetrain throughout its entire product offerings.   I'm sure the results in those cars will be even better than in my BMW i8.
We are averaging 56mpg overall
I've never experienced anything like driving the BMW i8 in my 35 years of driving life before. It's an intoxicating combination of power, lightness, refinement, art, driving dynamics, AWD, efficiency, comfort and stealth. It's the total package with each element making the other elements even stronger.

Silent running up to a destination like a restaurant or a hotel, and then the opening of the doors, causes the world to pause, jaws to drop, and exasperations of "what on earth is that!"   Stealth is king and a remarkably stark juxtaposition to the expectations of the very loud rumbling and high pitched revs that is the norm for such a car.   Folks just can't quite make it all work in their minds when they view the car in its silence.

It's a real privilege and an event to look forward to, geting in the car for each trip and each trip is an adventure, as opposed to a mundane outing.

I have yet to have a single glitch with our BMW i8 nor a service call, my service reminder stands now at 3900 miles with 7200 miles on the odometer.  I was concerned about this as I'm wanting to treat the i8 the right way, and brought the i8 into the dealership so they could double check on the service interval, they confirmed that I was 3900 miles from a service, however if I wanted to I could bring it in after 2000 more miles.

Our BMW  i8 gets a hand wash every three to four weeks courtesy of Mossy BMW of Vista and I really enjoy my 30 minutes at the dealership talking to the staff and checking out the new products.

I'm impressed and happy that after a year on the market and a quick check over at  that the asking price of used BMW i8's is holding at the same price as new i8s with an average asking price of $152,680

As a standard bearer for the new BMWi lineup of cars and as a platform that will spawn drivetrains for many future BMW's, I'm hopeful that my 2014 first model year, Electronaut Edition BMW i8 will retain a good value and hopefully become a valuable collectible in the coming decades.   I'm planning on keeping it forever if my financial situation allows, as it represents a personal journey for both Julie and I, beginning with the BMW Mini-E in 2009.

Our amazing journey to the future continues.


Tuesday, June 16, 2015

Religion, EV’s and Renewable Energy.

Politics and religion are often said to be avoided topics in conversation with others, if you ever want to be invited to the party again. 

Time to break that rule :)

With a flame retardant suit on, and with the knowledge that rough and tumble politics and political decisions are often written about in the context of EV’s and renewable energy, I’ll explore an ever increasing reason, why some are transitioning to a more efficient lifestyle, one that is largely unspoken and unwritten about.

Religious and spiritual beliefs.

There is a diverse multitude of reasons why folks transition to renewable energy and EVs: saving money, hi tech adopter, climate change, self reliance, energy saver, conservationist, stick it to the man, getting off oil, local air quality, a desire to not go to war over scarce resources and more.   

You can now add religious beliefs to that list.

Most EV and renewable energy enthusiast posses some of the above reasons, but not all.  Some are “spokes” motivated by a singular mission or belief, a singular force that drives them towards their choice.  Some are “hubs” having most or all of the reasons for their lifestyle choices.

The EV and Solar communities, (the two go together like chocolate and wine) generally are supportive of all the diverse reasons why folks make the decision to drive an EV and/or go solar.  The EV and Solar communities possess an all encompassing “big tent” attitude that whatever the individual reason, whatever the motivation, the “decision” to go solar or drive a car with a plug is more important than the “personal reason” the decision is made.   

Religious beliefs can also be accepted into that big tent with the knowledge that we all do not share every motivation including religion, for driving EV’s and or going solar.

Here are some observations on why I think it’s very important to talk about it, and why I think it will be a reason for many around the globe to make the decision to drive a car with a plug and power with renewables. 

  • According to Wikipedia, 80% of Americans identify themselves as religious with Christianity being the largest belief by far. That’s a lot of potential future EV buyers! 
  • On June 18th, 2015, Pope Francis will publish an encyclical regarding the environment and mankind’s relationship with nature. This will add a worldwide “morality dimension” to the scientific and political discussions about decarbonizing our planet. I believe this Papal Encyclical will be a very large consideration for many, and a huge driver of future EV sales. 
  • Many churches and beliefs are divesting from fossil fuel including the Church of England and the World Council of Churches representing 590 million members in 150 countries.  Driving an EV powered by renewables is the ultimate individual divestment from fossil fuel. 
  • This is a personal observation: In Southern California, more and more churches are putting solar PV on their roofs, with the desire to be better stewards of our planet. This decision is made with this stewardship desire as an equal or greater reason than the economic savings. I recently had a conversation with a gentleman that was on a church board representing 40 congregations in San Diego and Orange County, He enthusiastically reported to me that they recently voted to install Solar PV and electric vehicle charging infrastructure at all their church locations.

There are many great reasons to switch to electric transportation and renewable energy sources.  Religious beliefs can now be added to that list.  Our EV and Solar communities are quickly about to get a whole lot larger and more diverse.  

Welcome to the club Pope Francis and welcome to all faiths, all parishioners and all houses of worship around the world!  

Now is not the time to whisper in dark rooms to a similar few,  now is the time to raise our varied, collective, community voices as high as we can to as many as we can.

Electric transportation powered by renewable energy is the right choice.


As always, thanks for reading and I'm interested in hearing your thoughts in the comment section.


Friday, May 29, 2015

Month 12. Hello Future... we’re here.

Our yearlong journey, "Driving to Net Zero Energy" has now come to an end. Thank you to BMWi, ChargePoint, Inside EV's, Stellar Solar, the Center for Sustainable Energy (CSE)  and SDG&E, for following us and supporting us during this past year.

My hero is an imaginative and creative child.

Our two BMW i3’s and our home were powered by harvested sunshine from a small portion of our roof with zero gasoline cost and zero utility cost for the last year…for forever.    We did it!

We believe we are the first household in the world to do this with full documentation. We also believe that there are dozens, perhaps hundreds of other households who have accomplished the exact same thing without going though the painstaking detail and very public process of sharing private and personal information.

Why this scope & scale?

There’s something traditional, in an American sense, about a home and two cars in the garage.  We are a nation that came of age the past 100 years concurrent with the era of the automobile. For better or worse, our homes and cars are together entwined with the embodied energy of our built history. For better, we can now power both our homes and our cars with renewable energy, in our case with sunshine.  We can also effect change on this personal level of our own lives, it’s harder to do on a citywide or national scale.

“The inertia of the status quo, is a powerful foe of progress”  

There is safety and security in the status quo but there is no future, only a past.  

It is for this reason that we decided to do the Driving to Net Zero Energy challenge,  why I write, why I  share as broadly as possible our personal and private information, why I serve as a Planning Commissioner of the nations 5th largest county by population, so that I, that we collectively, can help “break the broken” status quo, and move ourselves, our families and our cities to a far better, richer, healthier future. 

The gas station down the street, the power-plant in the next city over, and the oil wells across vast seas and deserts, have served our households and transportation energy needs during the past 100 years. They are now giving way to the homeowner who fuels their own home and cars with electricity from solar harvested from the roof of their home.  An ecosystem of a dwelling, an energy plant and transportation all contained in one unit, enriching the owners whether a home, a commercial hub or a city.

As a society, we have arrived at a destination, an intersection of our historic calendar and our always-advancing technology prowess whereby today, our cities, our homes and our electric transportation choices can be powered by renewable energy generated by a homeowner.  During the next 20 years, our country and our individual households will see changes in energy and transportation that are hard to comprehend in their magnitude and benefits to our environment, safety and health, and to our household budgets. 

Our year in review:

Let’s start with a couple of 800 lb. gorillas and get them out of the way.

1.     Although we have no cost of energy or gasoline for our home and two cars, saving us about $8000 a year, we are not 100% energy independent.  We are grid connected; we have had a very slight amount of electricity use for the year and a small amount of natural gas use.   There is no economic reason to go any farther than below zero cost,  but half our goal is to be energy neutral, this has still not been reached.  Our cost are zero and our usage is de minimis.  You’ll see this in the charts below.

2.      If you think you can plan a year in the future, think again. Our year has unfolded with several unexpected events not foreseen during our planning for the year. 

We made a last second decision to host a Rotary International French exchange student for a year so that two young students, one from France staying with us, and one from Coronado going to France could have the experience of living a year abroad.  Another person in the household with a full head of hair and an energy hog hair dryer added to our annual total. I actually calculated her monthly (85kwh) energy consumption, I know, that's a little obsessive, compulsive.

We expected to drive 20,000 miles this year; we ended up driving 21,477 miles.

We lost a family member, priorities about energy savings we’re inconsequential during these months of care giving and grieving.

After three years of being a two EV household, after working with and Field Test driving for BMW during the past 5 years beginning with the BMW Mini-E, I had the opportunity to buy a very special one off Electronaut Edition of the BMW i8.
During the last 2 months of the 12 month "Driving to Net Zero" challenge, we were a three car household.  The BMW i8 took a couple of long road trips and it’s a very special collectible car that will see a road trip or two a year and a scant couple of hundred miles a month.   Our two i3’s remain our daily drivers. Our challenge was 20,000 miles a year in the two i3’s which we surpassed.   The BMW i8 (a plug in gasoline hybrid) is a dream and a collectible and we are fortunate to own such a car.

Even as a two EV family before the BMW i8, once or twice a year we would borrow a gasoline car for a long driving trip. We take the occasional plane flight, cruise ship, train, bus and taxi, all of which consume gasoline, avgas or diesel.  So we possess no "EV purity card" and never have, as the rest of the transportation network is not quite as advanced as our household.

We realize how fortunate we are in life, and that we are not the statistical norm. However in California at least, Solar PV is making its way to all income levels and housing types and EV’s can be leased or purchased for well under $200 a month.   Living Net Zero does not need to be done in a custom home with BMW’s in the garage.

Lastly, we think that’s what makes this "Driving to Net Zero" challenge so special. It’s a real home with real people, real lives that are wonderfully unpredictably complicated, covered over the course of a year.   It’s not an unoccupied home on a University campus built by a car maker. It’s not a theoretical calculation of energy use by a home builder or a University.   It’s real, it’s us, "warts and all" for a year.

Now our year of data in review  :) 

Julie is a more efficient driver, and a credit for the year of -$751

Our annual credit for unused electricity, $-751.57
Our annual gasoline cost for two cars, 21,477 miles, $0.00
Our annual natural gas cost, $279.89
Our annual total cost of energy $-471.36

Last year after four winter months we had used 1150 kWh of electricity.
This year after four winter months we have used -349 thanks to one
less person in the household and the more efficient BMW i3's.
We expect this trend to continue generating an extra 1200kwh
more than we use for this year, to offset our small Natural Gas use.

Our energy challenge began on May 15th, 2014, when we received both BMW i3's, the most efficient car in the USA.  Our annual true up bill from our utility begins every year on January 15th.  As you can see we are on a great trajectory for 2015 and we expect this to continue resulting in an overproduction of around 1200 kwh of electricity.  The stronger sunshine summer months are approaching.

Solar Panels occupy about 25% of our roof space as outlined in blue.
Notice all the roof projections were designed to be on the north side 
of the home, thus clearing the way for solar PV on the south side.
Our ChargePoint usage graph for the year.  Our ChargePoint CT 4000 was
installed the first week of June so a few weeks of date were hand tabulated.
It's a heartbeat of energy use. The gaps are mini vacations away from home.
A monthly view of the same data.

A total of 5061 kWh of electricity was used to drive 21,477 miles in two BMW i3’s.

Julie averages 4.3 miles per kwh 11,862 miles / 2717kWh
Peder averages 4.1 miles per kwh 9615 miles / 2344 kWh

We both have our own port and swipe our separate ChargePoint cards to activate
the individual ports. This is how we tabulate each car and driver separately.
Love the BMW i3's, that they plug into the sunshine on our roof.

When you live in a home and drive EV's powered by solar, every
aspect of emissions is reduced, thus improving the air quality for all.

Before our solar and electric cars, we had fun powerful but gas guzzling cars
and a high cost of gasoline and utilities.

Today, this picture and graph represent our cost. The $245 was
an estimated cost for nat gas when this slide was made several months ago.
It's a complicated formula that varies from utility to utility.
In our utility, any unused credit is not refundable.  Thus no check
for $751.  We did however receive a check for $36.68!
Like I said, it's complicated! The utilities set the slot machine payouts.

This was calculated when gas in our region was $3.50 a gallon.
Today's gas prices are $3.93 a gallon.
Now you see how I can afford to drive the BMW i8 :)

Our 8.5kw Solar PV system generated 13,546 kWh for the year. This equals 1593 kWh per kw system size.

A 3.18 kw Solar PV system (3.18 times 1593) would provide the 5061 kwh of power for both BMW i3s driven 21,477 miles.

The total cost of the 3.18 kw PV System is equal to buying gasoline for 2.82 years. An ROI of 35.4%

Driving the BMW i3’s powered by Solar PV, the cost per mile is $0.017 cents per mile. 

If advantageous TOU rates are factored in as our case, the Solar PV system size and cost would be reduced by 22%, the cost is $0.013 per mile.

Driving on Solar PV supplied electricity is 1/10th the cost of driving on gasoline.

In summary:

Thank you to you the reader for following us on this year long journey.  Thank you for your many comments and questions throughout the year.  One of the unexpected joys, and I am so fulfilled when I hear it, is the dozens of times in the past year folks have thanked me for writing and for inspiring them and giving them confidence to do similar, to what we have done.

Just take a small step, a small reduction in energy use or a slightly more efficient car or transportation choice if you can. You don't need to go all "Full Monty" to a make a meaningful contribution to improving your city and your budget for your family.

It has been an iterative process for us the last several years beginning with solar in 2007 and with two gasoline cars and a toe in the water with the BMW Mini-E in 2009 to where we are today.

Get started and change your world,  you can live and drive on Sunshine.

For more information about our systems and cars read the first post, Energy Challenge Introductory Article of this series below.


Friday, May 22, 2015

Our one year experiment of living and driving on sunshine is over!

The idea is a simple one.

"Harvest endless sunshine from a small portion of a roof to provide 100% of the energy needed to power a home and the two cars in the garage, with zero utility cost, and zero gasoline cost."

On May 15th, 2015 we concluded our year long Driving to Net Zero Energy Challenge.  It's hard to believe that our two BMW i3's are already a year old and boy did time fly!  I'll have an overall wrap up post about the year on June 1st.

Before then,  I'll carve out a couple of sections and focus a little more in depth on various parts of the effort.

We believe we are the first household in the world to attempt this with full documentation.  We also believe that there are dozens, perhaps hundreds of other households who have accomplished the exact same thing without going though the painstaking detail and very public process of sharing private and personal information.

Thank you to BMWi, ChargePoint, Stellar Solar and SDG&E, for following us and supporting us during this past year.  It is because of a very efficient home, a great Solar PV system (installed in 2007) and the BMW i3's, the most efficient cars sold in the USA, that we were able to attempt this effort.

We have also documented this effort at every turn, with our utility, our Solar PV generation, and with the ChargePoint CT 4000 charging station in the greatest detail possible. With the ChargePoint CT 4000, we are able to account for every kWh taken from the wall and used for the BMW i3's.

Data is king,  ChargePoint with the CT 4000 and soon their residential home charger the ChargePoint Home, allows the owner to see data on each charging session in detail, just like checking up on your bank account or your friends on Facebook.

A focus on the BMW i3's powered by Solar PV. 

Our BMW i3's in the garage

We're loving our BMW i3's and they have been a joy to drive all year.  They have been trouble and maintenance free with the exception of one service visit for each car to update the software and replace the KLE.

The cars are a blast and spirited to drive, especially off the line,  and are very practical for our semi-urban lifestyle.  Every morning they await us with a full charge ready for the days adventure.  One detail in particular that has been very impressive is that we have no door dings, dents or scratches after a year of duty on the roads.  Typically for us we collect a few door dings and the occasional scratch every year.  The carbon fiber construction and thermo-plastic skin appear to be a great advance in not only lightweight construction, but also in durability and appearance.

Just one funny anecdote.  Of course we race our cars against each other! Julie and I both have the BMW i3 bev model, so we have to see who's got the fastest car.  In the first race Julie beat me by a long shot and  I was sure that BMW had made her car just a little faster than mine.  We swapped cars and did the same race again...and Julie beat me by a long shot.   I have concluded that my extra 150lbs was the difference in both races :)  Julie may be able to go 0-60 in 6.5 seconds, but it takes me a few ticks longer.

Using our stats we collected every month for the past year, here is in detail how our cars performed powered by Solar Energy. That's the beauty of the challenge. These are all actual and real world numbers, not estimates or calculations.
Location is Carlsbad Ca. 

  • A total of 5061 kWh of electricity was used to drive 21,477 miles in two BMW i3’s.
  • Julie averages 4.3  miles per kwh  11,862 miles / 2717kWh
  • Peder averages 4.1 miles per kwh  9615 miles / 2344 kWh
  • Our 8.5kw Solar PV system generated 13,546 kWh for the year. This equals 1593 kWh per kw system size
  • A 3.18 kw Solar PV system (3.18 times 1593) would provide the 5061 kwh of power for both BMW i3s driven 21,477 miles.
  • 37% of our overall solar generation was used by our BMW i3’s,  63% was used by our home
  • It would cost $9540 to provide the solar supplied energy to drive both BMW i3's and subsequent cars, for 25 years (536,925 miles) 
  • Two gas cars @25mpg (average fleet mpg) would use 859 gallons of gasoline to drive 21,477 miles
  • Current cost of gasoline in San Diego Ca is $3.93 a gallon using 859 gallons of gasoline  is $3375
  • The total cost of the PV System is equal to buying gasoline for 2.82 years.  An ROI of 35.4%
  • Driving the BMW i3’s powered by Solar PV, the cost per mile is $0.017  cents per mile.  
  • If advantageous TOU rates are factored in,  the Solar PV system size and cost would be reduced by 22%, the cost per mile would be $0.013 per mile.
  • Driving on Solar PV supplied electricity is 1/10th the cost of driving on gasoline.
Average price of gasoline on 5/22/15

You can live and drive on Sunshine :)

Cheers and thanks for reading and commenting.

Wednesday, May 20, 2015

Tesla Powerwall, Does it make sense?

We'll get to the math below soon, but allow me a couple of rambling paragraphs as prelude.

Did it make sense in 1983 to pay $10,000 in today's dollar (adjusted for inflation) for the first commercially available cell phone, the DynaTAC 8000, that had a talk time of 30 minutes, took 10 hours to charge and worked in less than 1% of the United States?  

Did this make logical sense when you could during the same timeframe, walk into a Sears, buy a corded telephone for $19 that worked all over the world and that cost much less per minute to use?

History answers that question for us with a world changing YES, going from one cellphone in 1983 to over 7 billion cellphones in 2015.  What was once so expensive and so exclusive, is now in the hands of everyone, by the way with battery energy storage that keeps on improving.

So too I am sure, one day in the not so distant future, battery energy storage will be the hands of everyone for their home and their cars. Remember this cellphone example when I do the math below.

Did Tesla invent battery energy storage?  No. Did Starbucks invent coffee? No.

Love them or not, Starbucks “reinvented” coffee and convinced us it was ok to pay $2.00-$5.00 for a cup of coffee…everywhere…several times a day.

Get ready to say Tesla Powerwall in Tall, Grande or Venti sizes soon as Tesla reinvents battery storage.

If you have been following our 12 month journey “The drive to Net Zero Energy”  you’ll know that our family lives in a home and drives two BMW i3’s with zero energy bills and zero gasoline cost all powered by Solar PV. 

Let's take look at our energy use and generation for last year. A year that ended with a $~450 energy credit to us.

If the premise is that you can take energy from the sun during day light hours and then store it to use during non daylight hours, the Tesla Powerwall is a huge money loser for most Solar PV users at the moment, due to "Net Energy Metering" agreements (NEM) and Time of Use (TOU) rates.   

California and many other other states have NEM agreements and TOU rates for solar PV system owners.  In fairness to Elon Musk, he pointed that out in his presentation with his comments about how in the near term, emergency back up is the best utilization of the Powerwall.

The NEM agreement, simply allows you to sell excess electric energy generation to the utilities generated during the day or longer summer months at the same price that you buy the energy from the utility at night or shorter winter months.   At the end of the year, if generation equals use, the bill is essentially zero. The NEM agreements last for at least 20 years.

TOU rates are two to three times higher during the peak hours (see chart above as we generate more during peak period) than they are during off peak hours.  Most of the large cities in California will have peak rates averaging $0.35 per kwh average of summer and winter rates, off peak $0.22 cents and super off peak $0.15 cents.  Essentially it's a 2-1 sale by using energy at night.

In our example, being grid tied to the utility, the result is no utility bill or gasoline cost.   Many argue both pro and con that other utility users are subsidizing solar PV customers, but I'll leave that for another day. Let's just say if I went off grid those same folks would say that utility users have to pay more since I'm not paying to be tied to the grid that comes to my home.  Sometimes you just can't win.

If I used a Tesla Powerwall to go "off-grid"  I would not get the financial arbitrage benefit of getting paid for excess generation during peak hours thus instead of an annual credit, I would have no utility bill but a large new expense for the Powerwall.

How much of an expense to go off grid?

I would estimate that our home and our two cars use an average of about 30kwh a day.   Roughly 10kwh for the 2 cars and 20kwh for the home.  Most off grid folks recommend 4 times the use to cover winter storms and the lower sunlight months of winter.

So lets assume a 100kw battery system for our home and cars.  It's just a guess since Tesla did not release the price for their larger units, but lets say the price is $30,000 ($300 per kw) and another $10,000 for installation for a total of $40,000.  

Assuming a high cycle life of 5000 partial cycles or about 12 years, I would need two of these systems during the 25 years of the Solar PV panels lifetime.  Again assuming a reduction in cost of half, 12 years from now and minimal installation expense as it's a swap out, the second system will cost me $20,000.

That's $60,000 for 25 years which equals $2400 per year for an off grid setup.   Grid tied I have a $~450 annual credit. So the math does not add up, but remember that first $3,500 cell phone and todays 7 billion cell phones as a strong lesson here.  Do you think the first cellphone purchasers cared about the economics of the cellular phone call?

So it begins with battery energy storage and the Powerwall.  Not yet a convincing financial equation for most homeowners with Solar PV, but a technology that is sure to to usher in the future.

As a solar PV homeowner and a multiple electric car driver, energy storage is the missing piece and I'm very excited to see Tesla and the Powerwall tackle this issue.  Energy storage will be a great enabler of renewable energy and our transition to electric zero emission transportation and cleaner air for our cities.

Today for the Powerwall,  last mile installations far away from power-lines,  new infrastructure projects without the needs for power-lines and utility scale energy storage make the most sense.

In the near term, "rate shaving" as high TOU rates creep into the darkness hours of early evening and we use the battery to cover that small time frame of dusk hours will begin to make sense.   In the long term it will make sense for all of us as prices fall and the technology advances.

There are other bright spots in addition to battery energy storage as well.  Our cars can each hold 20 kwh - 85kwh  of energy and vehicle to grid applications are developing to use that energy for the home or the grid.  New solar PV inverters come with a separate 15 amp, 1500 watt circuit that can deliver 7 to 10 kwh of electricity when the grid goes down each sunny day.  This is similar in quantity of electricity to the Powerwall.

In closing...when you use that cell phone of yours  to make your next call...remember how it got here and where it came from.

First communications, and now energy and transportation,  all three can be thought of as "internets" and they're all going to work together in the future to solve some of our worlds most vexing problems.

Bravo Elon Musk, Bravo Tesla and the Tesla Powerwall.