Grid Parity for Solar PV: Important Milestone but not a Tipping Point

A recent study shows that solar electricity from photovoltaic systems has reached grid parity. The final peer-reviewed paper from this study has not yet been published, but a prepublication draft may be accessed here.  The study has already generated discussion on several websites (e.g., see here and here).

Achieving grid parity marks a significant milestone in the development. Although the authors of the study do not call it so, grid parity has been claimed to be the tipping point. Is it the tipping point—the point which marks an inexorable trend towards installation of PV systems over other technologies such as coal, natural gas, or nuclear? I think it would be premature to call it a tipping point, as doing so unnecessarily raises false hopes and undercuts credibility when reality does not live up to the expectations. Let us review what is really meant by grid parity and then we can decide whether or not to call it a tipping point.

A technology is said to have reached grid parity when the levelized cost of electricity, LCOE, produced by it is equal to the price of electricity that customers pay to the utility. Note that already there is an apples-to-oranges comparison. On the one hand we are talking about the cost of producing electricity, on the other it is the price that we pay for it.

There are many technologies for producing electricity each with its own set of capital and operating expenses, risks—which impact interest rates—and expected useful lifetime. Some require fuel use others do not. LCOE is a way of capturing these disparate factors and estimating the cost of producing a unit of electricity from a new facility. It is a tool to help power producers decide which technology to deploy to expand capacity. Conceptually the process is straightforward and entails estimating all the expenses for the lifetime of the plant and the total dividing it by the total amount of electricity expected from this plant. In practice though, details get in the way and muddy the waters. I found this discussion of LCOE to be particularly lucid.

Plants are rarely built with all installation costs paid upfront by cash. They generally require some type of financing, and these charges (principal and interest) as well as operational and maintenance expenses are incurred over time. Likewise, the income from the sale of the power is accrued over time. Net present value of these future expenses and revenues are calculated using a discount rate, which is generally slightly more than the projected inflation rate. For technologies requiring fuel inputs, projections must be made about the likely the future price of the fuel. The expected power output also requires assumptions about terms such as plant’s availability, useful lifetime and performance degradation over time. One of the key messages of the study cited above is that it is very important to use consistent and realistic values for these parameters when comparing LCOEs. The other point of the study was that if one uses realistic estimates for financing terms, useful lifetime, and performance of PV panels, the LCOE of solar electricity is significantly lower than many previous estimates.  It can range between 12 and 25 cents/kWh and thus reach grid parity in many locations.

The grid price for electricity for many US customers is between 9 and 12 cents/kWh, although the cost of producing electricity is substantially lower. Depending on their usage, the marginal cost of electricity for residential users can be as high as 35 cents/kWh. The cost of producing 1 kWh of electricity from coal power plants is often quoted as between 2 and 2.5 cents. This cost is not the LCOE from coal plants as it refers to only additional cost incurred by plants that have already been paid for. LCOE from coal plants is estimated at between 6 and 8 cents/kWh without carbon capture and sequestration. The economics of installing a PV system depend on whether one is speaking of residential systems or a utility scale system.

While it may now make economic sense for certain users to install PV at their homes, the LCOE from PV systems have to ultimately compete with LCOE from competing technologies. With relatively stable natural gas prices for the foreseeable future (ca. $4.00/MBtu), the LCOE from gas-fired plants is currently estimated at about 7 cents/kWh. Add to that their reliability, rapid ramp up, and relatively low system cost PV still has ways to go before it becomes the technology of choice for large scale installations. 

Misleading Headline

The headline of an article in LA Times declares, “Renewable power trumps fossil fuels for first time.”  No, it is not that more electric power is being generated from renewable sources than from fossil energy.  The article is talking about investments in power systems, and according to a recent analysis by Bloomberg New Energy Finance, in 2010 more dollars were invested renewable electric power systems than in coal-, gas-, and oil-fired plants; $187 billion versus $157 billion. 

The accelerated pace of investing in renewable power is good news, particularly when we realize how far we have to go. However, it is also worth asking what did we buy with those investments.  This article does not answer that except mentioning towards the end that 36 GW of wind capacity was added 2010. It turns out that globally about 92 GW of renewable energy capacity was installed renewables; 30 GW of large hydro, 17 GW of PV, a smaller amounts of solar thermal and geothermal systems.  The world also added a comparable capacity of coal- and gas-fired plants in 2010.  China alone added 80 GW of coal and India added about 20 GW.  Because of their higher availability factor, they are expected to provide two to three times more electrical energy for the comparably sized fleet of renewables.

Cost of PV Systems: Expectations and Realities

 I have recently come across several reports each of which has reiterated the fact that the cost of solar PV is plummeting: panels will soon cost less than $1.00/Watt and so will the installed costs (Ramez Naam); it will be cheaper to produce electricity from PV without subsidies than from coal (Mike Halper).  In view of these very encouraging developments, I am left puzzling that NRG Energy is installing a 250-MW PV facility with subsidies of $2.1 billion to cover almost all the costs (that translates to > $6.40/Watt) (NY Times).

Downloads and other links

Here are a few links to downloadable documents, presentations, etc. as well as links to video clips pertaining to A Cubic Mile of Oil.

Topic	Link
Errata	List of Errors in the First Printing
Presentation	Power Point presentation, 2011 CMO Presentation, 2015
Handout	A  one-sheet handout with pertinent facts
Radiation Doses	A Useful Radiation Dose Chart
Future Talk	A conversation about CMO (10 min)
U. Toledo lecture	A public lecture on CMO (60 min)
USGS lecture	Another public lecture (75 min)
Forbes.com	Editorial on our Energy Challenge
Financial Sense Newshour	An in-depth conversation with Jim Puplava
Synopsis	A 3-page article summarizing the book in Energeia

Batteries for Electric Vehicles

Advances in battery technologies over the past few years have been absolutely remarkable. When I was working on the section devoted to batteries and electric cars in 2008, nickel metal hydride (NiMH) batteries were the batteries available for cars like the Toyota Prius.  They used to cost about $1.00/Wh capacity.  All-electric car manufacturers like Tesla and Fisker (Fisker is a series hybrid not an all-electric car), who were making vehicles targeted for the high-end market, were offering lithium ion batteries.  Li-ion batteries have a higher energy density and are more durable, and they were the battery of choice for many personal electronic devices such as cell phones, PDAs, and laptop computers.  However, they tended to be very expensive.  I estimated their cost to about $2.50/Wh based on the information available at that time for smaller systems.  The price of the Li-ion batteries has dropped dramatically in the last few years—to about $0.40/Wh, and are now the battery of choice for electric vehicles. 

The all-electric Nissan Leaf has a 24 kWh Li-ion battery pack and has a base price of $33,000 (before tax credits); for reference Toyota Prius has a 1.4 kWh battery pack.  Clearly, the batteries cost a lot less that $1,000/kWh.  Likewise, the new gas-electric hybrid Chevy Volt has 16 kWh Li-ion battery, and sells for $41,000.   It is sized to allow users a driving range of about 35 miles on electric power alone.  The battery lifespans have also improved significantly, and they are expected to last 10 years and guaranteed for 100,000 miles.  

These improvements have changed the economics of driving electric vehicles.  According to the US EPA, Nissan Leaf consumes 34 kWh for 100 miles. At grid electricity cost of $0.10/kWh, driving the 100 miles would only cost $3.40.  A comparably sized gasoline engine car giving 33 mpg would cost about $12.00 at the current price of gasoline ($4.00/gallon).  If we add the amortized cost of the battery ($9,600), the cost for 100-mile drive would increase to about $13.00, still comparable to the gasoline case, and not substantially higher as was the case a few years ago.

Fukushima Disaster and Germany's Response

I am in Oviedo, Spain, attending the International Conference on Coal Science & Technology.  It’s good to reacquaint with friends and colleagues whom I have known for several decades.  My conversations with friends from Japan and Germany, prompt me to write this post on the nuclear power after the Fukushima disaster.

The massive earthquake and the awesome tsunami it engendered wreaked a terrible havoc on the people in Japan, particularly those living in and around Fukushima.  About 15,000 people lost their lives from the tsunami, and hundreds of thousand were rendered homeless.  The Dai-ichi nuclear power plant shut down in response to the earthquake, but it needed power to keep water flowing around the fuel rods.  Downed power lines meant that the plant could not receive power from plants elsewhere to keep the cooling water circulating, and since the tsunami had knocked out all the backup diesel generators, the plant had only a few hours of power from its batteries, not long enough to restore power connection.  Bad things happen to the light water reactors when the coolant is lost, and the Dai-ichi plant experienced a series of those: at least partial meltdown of the fuel rods, generation of hydrogen from steam reacting with hot metal, venting of gas pressure in primary containment to keep it from blowing, build up of hydrogen in the secondary containment, hydrogen explosion and release of radioactive materials. 

The Scale of the Disaster

Each day brought news of a worsening situation.  As events unfolded, comparisons were made with previous nuclear accidents.  Initial reports placed this accident below or at the same level of severity as Three Mile Island, level 5 on the International Nuclear Events Scale (INES) scale.  As more information became available, it was recognized that radiation released from the Dai-ichi plant was much larger and the incident was re-classified as a level 7 disaster; the same level as Chernobyl.  It turns out that 7 is the highest rating on the INES scale.

By placing Chernobyl and Fukushima at the same level, we lose the value of the INES scale, which relates to radiation released and not its effect on people or environment. We need a different scale if to rate disasters.  The situation is analogous to describing earthquake disasters using the Richter scale.  The scale measures the energy released from the ground movement—not the effect it had on the structures and people.  The 1989 earthquake in San Francisco registered a magnitude of 6.8 and caused the death of 63 people and rendered about 4,000 homeless.  The Kobe earthquake of 1995, although of a similar magnitude registering 6.8 on the Richter scale, was much more devastating.  It resulted in the death of about 6,400 people and rendered about 300,000 homeless. 

At Fukushima the primary reinforced containment did not fail, and held back most of the radioactive materials.  In the Chernobyl disaster there was no secondary containment, and when the only un-reinforced structure failed and particles from the core were dispersed into the environment by a large explosion. The cloud of radioactive materials was then dispersed by the wind over a large part of northern and western Europe.  In the Chernobyl disaster nuclear material there were at least 47 fatalities from acute radiation, hundreds suffered radiation illness, and 600,000 people exposed to low-level radiation causing an estimated 4,000 additional cases of cancer (lower bound numbers). In the Fukushima incident there were explosions from hydrogen in the secondary containment structures, but they were not carrying core particles. To date there has been no fatality from acute radiation, although a few brave workers have suffered radiation illness.  

Risk from Long-Tern Exposure to Low-Level Radiation

Understandably, there is much concern about the effect of low-level radiation on the people living around Fukushima.  The fear of unknown is palpable, and parents are mistrustful of assurances by the government and industry spokespersons.  Large areas were evacuated and radiation was detected in the food and water from that region.  A friend of mine who lives in the neighboring Ibaraki prefecture wrote to me asking for help in locating a Geiger counter so he could check the radioactivity in the food and milk his family is getting. A quick check on eBay showed many vendors selling Geiger counters and radiation dosimeters, and many listed options for "shipping to Japan."  Evidently my friend wasn’t the only one in Japan looking for this device.

I gained some perspective on the health risks of radiation while doing research for the Cubic Mile of Oil book.  I hope this perspective will be of help to the readers.  While there are health risks from radiation exposure, the anxiety about it also poses a health risk.  

An acute exposure of 1 Sv is barely noticeable, above that, people suffer from radiation sickness manifesting in nausea and hair loss.  LD50 of acute radiation is 3 Sv, and exposure to 10 Sv is generally lethal within a few days.  The workers in Fukushima were in danger of suffering from acute radiation illnesses; fortunately, their exposure levels were monitored and managed, and as far as I know, none of them developed symptoms associated with acute radiation poisoning.  The other concern from radiation is from long-term exposure to low levels, which can lead to cancer.  This concern is the relevant one for the people living in Northern Japan. The consensus of health professional is that an exposure of 0.25 Sv (or 250 mSv) increases the chances of contracting cancer by 1%.  This correlation is based on extrapolation of high-level exposure to very low levels, and does not allow for any self-correction or healing of the radiation damage by the body.  It therefore serves as an upper bound to the risk.

We are constantly bombarded by radiation from all forms of natural (and man-made) sources.  Living on earth entails exposure to about 3 to 4 mSv (milli Sieverts) per year, mostly from cosmic radiation and from rocks around us.  Over a 100 years of lifespan, a person would have therefore been exposed to 300 mSv of radiation and that would increase the person's chances of contracting cancer by a little more than 1%.  Now, cancer is a very common disease, and as such afflicts about 20% of the population.  

I was looking at the radiation levels in the different prefectures of Japan at the Japan Times website.  In Fukushima the levels are about 2.77 uSv (microSv) per hour, in Miyago and Ibaraki it is less than 0.1 uSv/hr and elsewhere about 0.05 uSv/hr.  A steady exposure of 0.1 uSv/hr would over a year amount to a dose of 876 uSv or 0.88 mSv.  Over a 100-year lifespan, this dose would add up to 88 mSv.  Since 250 mSv increase the chance of contracting cancer by 1%, the dose of 88 mSv can be expected to increase the cancer risk for the individual by about 0.3%; from 20% to 20.3%.

There are a lot of statistics here, and I am aware that statistics offer little solace when one is considering health of near and dear ones.  However, I sincerely hope, this information allays some of the concerns by placing the risks in perspective.  Remember that anxiety is also deleterious to one’s health as it increases the risk of a cardiac illness.  

Germany’s Response

Soon after the Fukushima disaster Germany announced it would phase out nuclear power. I wondered where the replacement energy would come from. Would it be a serious commitment to renewables? What storage technology are they going to deploy to allow for that?  Germany has installed over 44 GW of wind and solar capacity, and in 2010 generated about 96 TWh of renewable power out of the total electricity generation of 621 TWh. Commentators opined that Germany would be looking to importing natural gas from Russia and coal from the Chech Republic to make up for the 140 TWh contributed by nuclear power.  The increased use of fossil sources would run counter to the goals of CO₂ reduction.  However, Germany also exports annually a net of about 20 TWh of electricity, Could it be that between cutting back on exports and employing conservation strategies, Germany could avoid increasing consumption of fossil fuels.

Based on the data for the first half of 2011 from Germany’s Bureau of Statistics, which show that Germany was a net exporter of electricity Paul Gipe (Bloomberg, Sep. 27, 2011) tried to dispel the notion that Germany will be relying on increased imports.  I think it is premature to judge the net effect of Germany’s decision to close the nuclear reactors. Compared to the first half of 2010 when Germany exported nearly 11 TWh more electricity than it imported, in the first half of 2011 it sold only 4 TWh more electricity.  Further, during half of the first-half of 2011, the nuclear reactors were still operating. We will get a better sense of the impact when the final figures for 2011 are published.  Stay tuned.

Bio-sourced parts for Ford Focus

I recently saw an announcement that Ford and BASF teamed to make foam for the instrument panel of Ford Focus from castor oil.  The material allows them to offer industry's first seamless soft-touch instrument panel that is stronger and better-looking.  All that is good!  However, a quote that caught my eye was "...Finding a sustainable product that saves more than 5,000 barrels of oil for every 300,000 Ford Focus models produced in North America is a very exciting solution for all of us."

Wow!  That's 0.7 gallons per car; when each car is going to consume an estimated 10,000 gallons over its life in fuel.  They are getting excited about savings of 70 ppm!  Their emphasis on the displacement of petroleum is either misplaced, or it is a ploy to attract unsuspecting customers.