Posts

Showing posts from 2016

Cheaper than Coal

Image
We hear a lot that "solar is already cheaper than coal," but this is obviously just PR. To begin with, these two sources of electricity cannot be easily compared. They are different animals altogether. Coal is a 24/7/365 type of power. Solar is intermittent and unreliable. Coal produced electricity tends to be more valuable because it is produced when it is needed. Solar, on the other hand, just dumps energy into the grid whether it is needed or not. Also, for the most part, solar PV does not allow the retirement of any conventional electricity capacity because at any particular moment the output from solar is zero and thus the conventional power plants have to supply the required power. At higher latitudes, the annual insolation variation can be extreme. For example, in Germany the insolation in July is close to ten times higher than during December. Additionally, Germany tends to require more electricity in the dead of winter. To be able to compare apples ...

Talking Straight

Image
In the energy discourse we are sometimes very careful but hey, once in a while we have to talk straight. Here is what we have to say respecting some energy sources: Fracking: yes, it creates earthquakes (sometimes). However, since natural gas mostly replaces coal, this is the fastest way to reduce CO2 emissions (and increase methane ones). Also, renewables need reliable, dispatchable pairing power plants and natural gas is ideal in this application. Nuclear: there will be more nuclear power plant accidents. Let's get over it. Yet, in spite of the future accidents nuclear will almost certainly continue to be the safest energy we have. The greatest danger seems to be to overreact and order evacuations when they are not really needed. There is an inherent danger in modern life (just like in flying in an airplane) but hey, we are much, much better off than we were in the past. Oh, and by the way, nuclear is very low CO2. Lower than solar and a match for wind. Are you listen...

Energy Transitions

Image
According to Vaclav Smil, anything below 5% of global total primary energy supply (TPES) can be considered a marginal energy source.  Using this marker, today we have the following energy sources that can be considered non-marginal: Oil Coal Natural Gas Hydro Nuclear  Oil Price widget to work Currently, wind is at 1.24% and solar  at 0.25% of global TPES, thus both are deep into marginal territory. Energy transitions take time and the number of years required to reach penetration thresholds tend to increase with each newer energy source.* The reasons are mainly these: The larger the overall energy market, the bigger the absolute amounts of energy the new source needs to supply. The advantages of subsequent energy sources keep diminishing. In particular: coal is much better than wood. Oil is better than coal in transportation uses. Natural gas is only better than oil in say, stationary uses like space heating, industri...

I Read the News Today, Oh Boy!

Image
Tired of being demonized by the green fringe and by the media in general, a secret meeting of the most important oil companies CEOs took place during the weekend.* They decided enough is enough so, unilaterally they have suspended all oil deliveries immediately and for an indefinite period of time. The world's reaction was swift and brutal. The news services are currently overwhelmed so we only know a minute part of what this decision has triggered. Here are some of them: Airlines do plan to operate their flights on Monday, but no new bookings are being accepted at this time. Among other things, this means travelers are being stranded all over the world with no easy way to go back home. The revenue of the airlines will quickly drop to zero and their financial position will deteriorate rapidly if the oil flow is not restored fast. State oil companies are not all participating in the boycott but the price of oil has skyrocketed already. Frantic traders have pushed the pric...

Cost per KWh

Image
Let's be careful when we see published charts with the generation cost of renewable energy (we'll be reviewing here solar and wind, not hydro which can stand by itself and provide reliable output).  We need to understand the following before accepting numbers at face value: 1. The value of energy depends on the time of the day / year that is is produced. Reliable and dispatchable energy tend to command a higher price in the market. Energy that is "dumped" into the grid can have little value or even a negative one (the grid needs to be paid to accept that surplus energy). 2. Bar some small off-grid operations, renewables need a pairing power plant in perpetuity. Thus in the cost of the system we have to add both the cost of the renewable installation PLUS the cost of the reliable power plant. In other words, renewables are almost always a duplicated investment and thus by definition have to be more expensive than a coal or natural gas power plant by it...