2010 Review & 2011 Look Ahead

Since 2007 I have been driving an electric vehicle, powered by solar panels on the roof of my house. Each year I look at how much energy my driving used and how much the solar panels generated. I want my EV transportation to be better than net zero. So how did 2010 do? Let's take a look and then see what will change in 2011.

In 2010, the solar panels generated 3575 kWh. That is enough energy to drive my electric truck 5100 miles. I drove my EV only 4506 miles. This means the PV system generated 425 kWh more than my driving used; yet another year of free driving. 

Now that the first Chevy Volt and Nissan LEAF cars have been delivered, there is a lot of press about the coming wave of electric vehicles and how they could overwhelm the grid. Our "EV driving" home does just the opposite. We supply power to the grid during sunny days when the air conditioners are running and charge the EV overnight. We supply energy when it is most needed, and withdraw it when there is a surplus. This helps to stabilize the grid, not bring it crashing down.

Sure, not everyone that buys an EV will get solar, but once I was driving with electricity, the source of that electricity mattered more than it ever had when I flipped on a light switch. And unlike with gasoline, I had a choice to produce it myself. I hope this awakening experience is a common one in the next decade.

One final note about 2010 before we look to the future: Our PV system's 2010 production was below 2008 and 2009's output by ~6%. There are two reasons, first the system was offline for 31 days starting in late January when the house painters sprayed paint into the inverter exhaust vent and killed it. Our inverter manufacturer, SMA, was very cool about it and gave me a refurbished replacement unit for free even though this was clearly not their fault. The second reason for the reduced output was the predominantly cloudy weather in May and June of 2010 when compared to the previous two years. In short, 2010 had a cloudy, rainy spring.

Looking ahead to 2011, there is one big change planned. I have ordered a Nissan LEAF. In early December I was told the car should arrive in 4 to 7 months. This means I should get the car, my first brand new car ever, before my birthday in July. This car will change my EV energy consumption in two ways. First, my heavy non-aerodynamic induction-charged truck uses about 700 Wh per mile. The Nissan LEAF is rated to use 340 Wh per mile for 73 mile range by the EPA. With a little hypermiling, I think I'll be able to use only 250 Wh per mile for a 100 mile range. This means that I'll be using less than half the energy per mile in the LEAF than I am using today. On the flip-side, with the longer 100 mile range of the LEAF compared to the 35 mile range of my truck, I'll be able to drive the LEAF far more. It will be interesting to compare energy use of these two vehicles and how the longer range changes my driving habits.

May 2010 PV & EV Report

Tesla Roadster Test Drive in Portland May 2010

The Seattle sales office of Tesla took a little road-trip down to Portland and I was lucky enough to get to drive a Roadster. The picture above is of my friend Jim as he pulled out on the start of his test drive. See that big smile? That is known as the EV-grin. Driving an electric vehicle is a blast, driving a sports car is a blast, putting the two together and you are sure to smile.

Excluding the Tesla drive, I logged 446 miles of EV driving this month, using an estimated 320kWh. During the same time our PV system had its best month this year and produced 475kWh of energy. Driving on sunshine is an easy thing to do.

April 2010 PV and EV Report

April 22nd 2010 Earth Day 

In April, our little solar photovoltaic system quietly generated 402kWh. This is significantly better than April of last year when our system was down for 20 days and we only generated 129kWh. But we also edged out April 2008, when the system was only a few months old, which yielded 392kWh.

As for electric car driving, I logged 417 miles using 292kWh. The solar panels generated more than the EV used. I drove for free.

This month I put down a $99 deposit on a Nissan Leaf. If I do get one in December, it will use about one third of the electricity as the Chevy S10 Electric that I currently drive. There are two primary reasons that the Leaf is more efficient: one, it is lighter and two, it is more aerodynamic. Neither of these should be surprising. The Leaf is using newer lighter Lithium batteries compared to the Nickel Metal Hydride batteries in the S10. The Leaf is estimated to weight 2800 lbs. My S10 weights 4200 lbs. As for aerodynamics, the Leaf is a purpose built electric car. Whereas, for the S10, GM took the existing gasoline truck and retrofited the EV1 drivetrain into it.

Here is to the sunny summer months ahead and watching the meter spin backwards!

Wooden Shoe Tulip Festival in Woodburn OR, April 2010

March 2010 EV and PV Report

Spring is here and the solar panels are starting to produce the juice. In March, our little PV system generated 294 kWh. That is enough to run a CFL for nearly 200,000 hours. Since its late 2007 installation, our system has generated a total of 8.1 megawatt-hours. We passed the 8MWh milestone on March 21st, the 2nd day of Spring here in the northern hemisphere.

For my EV driving, I logged 472 miles in the Chevy S10 EV, using an estimated 300kWh. This is nearly equivalent to what the panels produced. This means that, as it continues to get sunnier and the days get longer throughout the summer, we'll be generating more power than the EV driving uses.

The big new in electric vehicle for March is that Nissan announced the price of the LEAF. It is $32,780. However, there is a $7500 federal tax credit bringing the price to 25,280. And additional state incentives are offered in California, Colorado, Georgia, Illinois, Louisiana, Oklahoma, Oregon, South Carolina, & Utah. In my state of Oregon the incentive is $1500, bringing the price to $23,780. In California, the state incentive is $5000 making this 100 mile range EV only $20,280. That is cheaper than a Prius and far cheaper to "fill up".

February 2010 EV & PV Report

Each month, I have been reporting how much solar energy our solar photovoltaic system has made and how much energy I have used driving my electric vehicle.

In late January, our inverted died. It is still under warranty, but because it had paint on it from when our house was painted, we were not able to cross-ship a replacement. Rather, the painted inverter had to be shipped to the manufacturer, repaired and then shipped back. Technically, the paint voided the warranty but the manufacturer was still willing to honor the warranty as long as we were willing to keep the painted case. That is good customer service.

The repairs were not quick and a shipping mix-up delayed the return even longer. Our inverter was not back in operation until Feb 26th. That is 38 days that we were offline, so there is very little PV energy generation to report. But I am glad this happened in February instead of the more productive June-August months.

As for EV driving, I logged 345 miles in the Chevy S10 EV, using an estimated 242 kWhs.

January 2010 EV and PV Report

January's big news is that our inverter has died. This is the second one that had gone belly up since we had our system installed in November 2007. When I called the installer, they asked what brand and model it was and they were surprised to hear that it was an SMA since they don't often have to replace the SMA inverters.

To complicate things, they were not able to fix it here onsite and they were not able cross-ship a replacement. We had our home painted last year and part of the inverter was accidentally painted. This means that our painted inverter must be shipped to SMA, be repaired, and then shipped back to us. The inverter died on the 19th and was taken away on the 25th and it is still not back.

With this month's limited up time, the system only generated 35kWh. This is significantly less than Jan 2009's 123kWh. When the inverter is returned, perhaps I'll try to remove the paint so we can cross-ship it, if this ever happens again. I am glad that it has a 5 year warranty and I hope this is the last problem that we have.

As for electric vehicle (EV) driving, I logged 326 miles using an estimated 228kWh. With the cold weather and the 11 year old batteries, they started to "complain" (battery life light) near the end of my 20 mile commute even though I had more than 50% charge left. So during the coldest week, I drove the Honda rather than the Chevy S10 Electric. This also gave me 4WD which I needed on one of the snowy days.

Next month I'll report the reinstall of our inverter.

2009 PV & EV Report

2009 Solar Power and Electric Driving in Review

2010 is here. 2009 is now in the books. Each month we look at how our photovoltaic (PV) system performed and how much the electric vehicle (EV) used. Let's review 2009.

We have a small PV system on our home in Oregon. My primary commuter vehicle is an electric Chevy S10 truck. On an annual basis, the PV system makes more energy than the EV uses. Which means, I drive for free, cost free, & pollution free.

In 2009, the PV system generated 3799 kWh. Of these, 917 were fed back into the grid and 'banked' for our use later. 2009 set one record for our system. June 28th generated 25.54 kWh, this eked past the previous record of 25.52 held by June 15th 2008.

As for driving, in 2009 I logged 4909 miles in the EV. This used an estimated 3400 kWh.

So the PV system generated ~400 more kWh than the EV used. And the bulk of the energy were made during the summer and so helped to alleviate the stress caused when the air conditioners were on high. Whereas the EV was charged overnight when the grid was not stressed and the winds were blowing through the Columbia gorge, turning the many turbines there.

Here is looking forward to a great 2010. Solar lease programs are now available in many states, so you can get a PV system of your own for little or no start-up cost. And 2010 could be the year that affordable, mass market EVs hit the showroom. So you too can drive on free fuel.

November PV and EV Report

November went out with a solar whimper as the final day of the month was foggy and generated a mere 1.2 kWh. Our panels generated 119 kWh for the month. This bested November 2008's result of 101 kWh.

I logged 465 miles in the electric vehicle, using an estimated 325 kWh.

This brings 2009's total energy generated to 3.7 MWh and EV energy used to 3.0 MWh.

October 2009 EV & PV Report

October's yield of electricity from our solar photovoltaic system was 228kWh. October last year was slightly more sunny at 250kWh.

Our total generation for the year is up to 3581kWh and our total since the November 2007 power-on to 7542kWh.

My electric vehicle driving for October logged 510 miles using an estimated 360kWh.

Year to date, EV driving has used ~2,689kWh. This is less than the 3581kWh that the PV system has generated. Drivin' on Sunshine.

September 2009 PV & EV Report

On Tuesday, September 22nd Autumn officially arrived at 2:18 p.m., Pacific time. Fall is here, the trees are getting decked out in glorious colors and birds are starting their migration. Halloween and cooler temperatures are just around the corner.

The days have become shorter, our PV system generates noticeably less energy than it did this summer. This month we generated 402 kWh, compared to the 618 of July.

Sept EV Driving
Distance 436 miles
Energy Use est. 305 kWh

Sept still had about 100kWh of surplus energy generation.

For the year we have generated 3353kWh and my EV driving has used 2332kWh. This leaves a surplus of 1256kWh for driving on sunshine through the winter months.

August 2009 PV & EV Report

Summer is waning. The days are slowly getting shorter. Our best solar production days have dropped below 20 kWh.

In total, our PV system has generated 6.9 megawatts and 1.6 of those megawatts were pumped into the grid during peak demand.

Our PV system generated 506 kWh in total for August. This is better than the the 474 kWh of Aug 2008.

For electric vehicle driving, I logged 209 miles in my truck using an estimated 146 kWh.

For the year, the PV system has generated 2950 kWh and EV driving has used 2000 kWh.