The battery gap

I explained to a friend this week my concept of “battery gap”.

He thinks batteries will not “be enough”, are “too far away” and “too expensive” for grid energy storage… Well, we’ve heard that old story before.

We heard that old belief that solar energy would never be competitive or only represent a small portion of energy generation, right? Or the one that grids had an inherent limit for absorbing renewable power (yes, some people once said it was 15%) Or that to reach a high degree of renewable penetration, the land use would not leave space to grow food… And such.

Well, the DOE has published an update on the accelerated escalation of LEDs, wind, solar, EVs and batteries. The graphs and the facts are impressive.

The difference in price for renewable energy Vs conventional grows quickly. So there is growing “space” to pay for energy storage. We could represent as follows: Sigue leyendo

Sailing 100% renewable

You might have read an old post on electric boats and sea energy harvesting before. I described then, electrifying boat transport as one of the ways to make islands 100% renewable.

Electric sailboats have a lot of sense, and are becoming more and more popular. It’s a fantastic sensation to sail, without the sound of a motor, and for many of us, turning the diesel engine on is to be avoided as much as possible. Moreover, even when the engine is only used for a little time, we strongly feel the pollution.

Precisely because for a sailboat the engine is not used that much, having electric propulsion and battery storage is very reasonable. It can be charged at the normal port outlet, regenerating while sailing, or with a small wind generator and solar panels. Compared to the need of refueling at a port gas-station, the convenience is increased greatly, and also the cost to the owner.

Maintenance of an electric motor is simpler because of less moving parts, the size of the motor is reduced, and the battery can be placed as ballast, incorporated in the hull. Sailboats already have batteries and often the motors have to run just to charge them. By increasing the size of the batteries and having renewable charging (solar/wind), this is automatically taken care of.

Besides, the performance is increased, having more torque at lower rpm, and electric motors are more efficient that the internal combustion counterparts.

Finally, regarding the noise, see this video comparing the diesel engines to electric. Together with the smoke/pollution, this is the most dramatic difference.

In summary, it will amaze me if in 5 or ten years all 95% of all new sailboats are electric. And I hope to sail on one of those soon.

20160730 Sunset desde barco

Sunset near Cala D’Or in Mallorca

If Energythaca were an island, sailing there would be on a sailboat. That was the image on my first post on the blog.

I guess it is an appropriate post arriving from vacations…

Upcycling sun-tennas

The following picture was taken in Casablanca from the Kenzi Tower one month ago. It isn’t the best example, though, for example, in Cairo, it strikes more to the eye.

What do you see?…

Antenas techo

Actually, there are approximately 200 TV antennas on the roof-tops. Let’s zoom in a bit:

Antennas 25 In this portion, corresponding to one building alone, you have around 25 units.

With the advent of cable television, wireless video streaming and other technology, these antennas could soon become stranded assets in many countries. Imagine how many could be left useless and need recycling. While thinking about asset utilization and the sharing economy, I couldn’t help but think:

What can they be used for instead?… Sigue leyendo

Capacity first?

…then Reliability, then Efficiency?

Developing an electrical network is a question of priorities. As is developing anything I guess… Which priorities do you think are most important?

You probably agree that the first step in building an electrical system is bringing access to electricity to most of the population, right?

Capacity to efficiency

This might seem solved, but in reality, access to electricity is still far from being universal. Still 1,2 billion people don’t have access to electricity. It’s in fact part of sustainable development goal 7, and, actually, the road to SDG7 is the road to Energythaca.

While building additional lines and power generation units to solve access to electricity, the values of reliability and efficiency are normally not on the top of mind for system planning. What if access to electricity is provided by renewable microgrids, would values like reliability and energy efficiency be achieved at the same time? Sigue leyendo

Future superavits in Energythaca

On one hand, the rise of renewable energy, even before the 100% goal, will bring superavit of power. This means there will be excess power that is not required in the system. It already is happening and it will be even more so. This power can be stored, but of course, using it directly is more efficient and thus, preferable.

On the other hand, the penetration of robotics and software will change the jobs available for humans, as is in discussion in Davos these days. This means there will also be a superavit of productivity.


Overflow. Image from Andrea Kratzenger on

We will have Superavit of Power and Superavit of Productivity, that we must use wisely to Sigue leyendo

The grid as an emergency supply?

It’s official. Finally Spain has the most toll-intensive consumer power generation (what is called self-consumption) law in the world. The so-called “sun tax” is in place.

It is important to understand the worries of the regulator here;

Given the high fixed costs of the system, further reductions of electricity demand (as with self-consumption) increase the price of energy in a Grid independence cycle. The goal of increasing the toll on self-consumption is to ensure the system costs are covered, delay the implementation of self-consumption (starting in the islands and small systems), delay consumer energy storage (in fact it is also a “battery tax”) and (try to) avoid further political problems. Of course, it is not the best solution, academics and regulatory experts agree that politically fixed costs that have to be paid by all citizens shouldn’t be in the tariff but evenly paid from the nation’s bugdet (like the extra-costs for electricity in the islands).

Image by Cancia Leirissa on

“Grid Emergency Exit”                                                       Image by Cancia Leirissa on

What are the consequences? Rising prices, and the fact that fixed costs (for the contracted power) are surging, push the active consumer to look for the following solutions:

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Why I supported GravityLight (twice)

The concept of the GravityLight is simple and yet very innovative. It consists in a light powered by gravity, it is charged by lifting a weight and letting its descent run the generator and the light.

Of course, it is only possible now thanks to the LED lights and other efficiency gains. With old light bulbs, the duration of the same concept would be ridicule, but now, a simple lift of 2-3 seconds can provide for almost 30 minutes of light.

Gravity Light Image from Wikimedia Commons

The running costs are null, and compared to the alternative of kerosene lamps, the impact is enormous in reducing costs, environmental impact, as well as reducing fire risks and negative consequences of smoke on the health of the users….

Sigue leyendo