News of My Canadian Pharmacy

Photovoltaics Comes of Age

Solar panels are cheap enough to become a major component of green energy.
Originally posted at: MIT Technology Review

Zweibel-KenThe United States has supported research into photovoltaics for almost 40 years, recently with a 30 percent investment tax credit. Japan instituted incentives in the 1990s, when photovoltaics cost at least five times as much as residential electricity. In the new millennium, Germany instituted incentives an order of magnitude larger.

Thanks to these efforts, the cost of photovoltaic modules has dropped 40 percent in the last 18 months. Photovoltaic electricity now costs about 15 cents per kilowatt-hour in the best sunlight. That’s only twice the cost of wholesale electricity and wind. Costs are expected to continue decreasing, and electricity is worth more during the daytime than at night. That means this technology is finally cheap enough to become a significant element in plans to combat climate change and oil dependence.

Solar for “Everyman”

ECONOMYSometimes I am asked the number of jobs solar will produce, and people are often disappointed when I point out that solar PV can operate without on-site labor. It’s as if they equate adding extra useless jobs with being green. Of course, we are trying to minimize the jobs so we have economical solar electricity…BECAUSE THAT IS WHAT WILL HELP OUR ECONOMY, not the jobs watching solar panels in the desert.

Have people forgotten how painful it is to have a terrible balance of payments, with our money going to oil dictators who hate us? Now that’s what I call a loss of jobs. Solar is about not sending our jobs abroad. (Of course, I am assuming we have the sense to deploy electric cars to use solar to avoid imports.)

The Arithmetic of Solar Royalty Trusts

Government bondsIn many ways, owning a PV system should be a dream investment. It promises dependable cash flow for an indefinitely long period of time, even a century, with little underlying market risk. It could be as good a definition of ‘risk free’ return as government bonds. Government bonds still face the challenges of national default; and PV, the challenge of a price drop in electricity. Maybe the PV is more dependable?

The basis for this is the two almost unique aspects of PV systems that are hardly ever fully exploited or even understood:

It uses no fuel, needs no on-site labor, and may have no moving parts (and thus has negligible operating costs)
The basic parts either last indefinitely (the PV module that converts sunlight to electricity) or can be replaced with nominal maintenance costs (the inverter that takes DC electricity and makes it ready for the AC grid).

Is Bad News Better than No News?

NewsMany times the articles on PV in the mainstream press are terrible. One would like to be kind and say that the non-expert authors are doing the best they can. Unfortunately, there’s a common theme in most of the mistakes they make – sensationalism. So deniability of responsibility is not so “plausible.”

I guess it’s no surprise. The media, which is all about “image,” uses sensationalism when it can. Sadly, this perverts their role as a source of believable information. They become advertisers, if only for themselves.

As an example of a really terrible article, let’s take “Thin Film Solar Panels Take A Giant Leap Toward Affordable Renewable Energy,” by Nate Lew of coolerplanet. Unfortunately, I found this article highlighted on Google News and also picked up by a SEIA newsletter and the NCPV Hotline. So these articles do get shared by others, who (like Moody’s did for bad debt) give them a patina of reputability.

We Love Our Cheap Modules

Today I saw a newsletter proclaim that some polysilicon modules could be purchased for $1.11/W.

Six months ago I wrote a blog called Buying PV without Getting Ripped Off. In the October 22, 2009 post I said:

“This is as much as anyone should pay for these systems in 2009:

$/W Installed 2008 2009
Residential $8.1 $5
Commercial $7.7 $4.7

Does It Matter that Something Can Be Cheap a Long Time from Now?

public health infrastructureI do connect this with the financial crisis. We seem to have become a world of people trying to cut corners and have it all now. The bankers sell hyped products for the fees and live high on the hog. Societies pump up debt to have it all now, and go on doing it until they reach a point of no return.

In Haiti, they paid a huge price for not having adequate building codes and building structures, all of which take money in advance.

In many developing countries, it is the absence of public health infrastructure like clean water and sewers, not to mention roads and dependable electricity.

I hear people say that doing things well is equivalent to being a fool. Their message is that it is better, smarter to do things poorly and get away with it. Maybe it was better when only a few people believed this, and society called them criminals.

The Future of Solar: It’s a Lead Pipe Cinch

coalWe are not competing with coal to make electricity from solar. We are replacing coal. This is not a competition with coal in the marketplace on a cents per kWh basis – this is a replacement of a harmful infrastructure. Coal, like lead pipes, is a harmful infrastructure.

We get very confused about competing in the marketplace for the electricity customer. But that is not happening. Instead, we are telling the electricity customer, “You are being poisoned by your lead pipes. What are you going to do about it?”

We are not waiting until coal power plants retire. We are turning them down and turning them off.

Land Needed To Make All Our Electricity with Solar Photovoltaics

electricity with PVA number that comes up frequently is the “what is the percentage of US land needed to make all our electricity with PV?”

The answer is about 0.7%: approximately a square 160 miles on a side (or 25,700 square miles); or 260 km on a side (66,800 km2).

The assumptions needed to calculate this are:

  1. The efficiency of the PV system (because that defines the area needed)
  2. The fraction of land the modules cover within the deployed system (packing factor)
  3. The output in kWh per installed W, which depends on the sunlight, tracking or not, and other losses within the system.

These numbers can vary quite a bit. For example, system efficiencies are between 5% and perhaps 15% at this time, and as they evolve, will almost certainly rise. Traditionally one is safe to choose 10% as the system efficiency, knowing full well it is likely to be better.

Why Utilities Don’t Buy Solar Energy (and why they do)

cost-effectiveUtilities don’t buy solar energy to provide energy to their customers. It’s too expensive and too unreliable. They don’t even buy wind for their customers, even though in most cases it is very close to being cost-effective. Neither of these intermittent sources suits their needs, either in price or dependability.

But they do buy solar and wind. They are trying to reduce their carbon dioxide emissions, and to a lesser degree, diversify their sources of electricity in case of fuel price shocks.

They are required by state and Federal regulations to buy wind and solar.

It’s really a simple equation. If –

Federal and state requirements – Added cost of electricity – Intermittency and transmission penalty > 0,
then they buy solar and wind.

How Much Could We Save If We Harness Solar and Wind with Electric Vehicles to End Oil Dependence and Eliminate Carbon Dioxide as a Problem?

electricity3We might save money if we harnessed solar and wind to displace all our coal and all the gasoline used for light duty vehicles (cars, SUVs, pick-ups). Let’s see how this works.

The US uses about 4000 TWh of electricity, and about half of that comes from coal (about 2000 TWh/yr from about 23 Quads of primary energy).

Our light duty vehicles require 17 Quads of oil, but only 3.4 Quads of it actually gets to the vehicles and moves them (20% efficiency from oil to movement). At ~300 TWh per Quad, this is about 1000 TWh of energy. If we did it with electricity and assumed 25% losses (electricity to batteries to motors to movement), we would need about 1333 TWh to move our light duty vehicles without oil. The total to displace both oil for cars and coal would be 3333 TWh. Let say this takes 25 years, so let’s assume 33% more demand by then (perhaps not warranted, since we may be saving energy, but just to be conservative) – that would be 4444 TWh in 2035. (This should be rounded, but it’s such a charming number, we’ll use it as is.)

So how much would this cost? Let’s do half with solar, half with wind.