Publication: Charging island homes

Do you think islands can benefit from the use of Electric Vehicles?

It’s quite reasonable to agree on the benefits.

Because of the limited distances, because of the availability of renewables, lack of local fuels and high energy dependence, and because of the environmental impact, electric mobility apparently fits there like a glove.

Besides, resiliency to face weather events by storing energy in the vehicle, and reducing peak electrical demand on normal conditions seem to be economically beneficial.

kreta-1364084 car island

Image taken in Crete by Repsaj on freeimages

The research we recently got published in Energy, focuses on the effect of using the vehicle’s energy to charge the home at peak load and charge the vehicle* during valley.

This is what we found out…

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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

“Baseload” is an obsolete pre-energy-transition concept?

“Baseload” is so much twentieth century… It is a concept widely used when demand was not flexible. When there was an uncontrollable consumption and industries were not adapting their production to availability of abundant energy. When the goal was to have nuclear and other conventional power plants running 24/7.

In the twenty-first century, the demand curve is not going to be flat, but is going to be variable and smartly adapted to supply of renewable energy.


The “base load” game. Image from Maria Yan (Yanovski-55776) on

Let’s look at the energy demand to challenge this concept…

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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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From 0 to 5-star Microgrids

Every building, office or home is a microgrid.

The question is, how good a microgrid do you want it to be?

Here is a simple 5-star rating for microgrids, an approach for anyone to understand;

You get one star for adding each of the following technologies:

1. Control

2. Generation

3. Electric Vehicle charging

4. Energy Storage

5. Microgrid Islanding functionality

Star Microgrid

A normal 0-star microgrid is a conventional building or home, with no automation or else.

It happens you upgraded your home and installed a smart thermostat for electric heating/cooling? Sigue leyendo

Flat? or wavy?

Smart grids are supposed to flatten the demand curve by reducing peak power (i.e. with demand response) and filling valleys (i.e. with EV charging). Price arbitrage using local energy storage is another driver for a flat demand curve.

So do you think in a few years the demand will be completely flat?

I bet it shouldn’t, let me explain why…

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