NZEB + EV: The decarb combo

Are you aware of these stats?

  1. Buildings account for 40 % of energy consumption and 36 % of energy emissions (EU data)
  2. Road transport accounts for 25 % of energy consumption and 20 % of energy emissions (EU data and EU stats)

Then, what happens when we combine NZEB buildings (net Zero Energy Buildings) with local renewable generation and EVs (Electric Vehicles) charging in these NZEB?

NZEB & EV.png

It’s obvious… -> We can decarbonize 65 % of the energy system!* Sigue leyendo

Not so sustainable, after all?

Finally sold my car!

Yes, I was considering to buy an EV, as I discussed in the post “To EV or not to EV”. But, for the moment I just sold my car and will try to be “car-less person”. At the end of the day, using public transport, car-sharing (we now have car2go in Madrid and it works great) and the bike is clearly more sustainable than owning any vehicle. (Well, and also borrowing my wife’s car sometimes…)

Parte trasera coche fino

But: I sold it. Which means my 15-year-old diesel guzzling 7-series BMW will still be consuming +15 l/100 km and emitting lots of particles and CO2 pollution. Depending on the distance the new owner will drive, it might be more ecological than him buying a new, more efficient, one. That’s because of increased asset utilization and vehicle construction sunken emissions. However, it might be that the most ecological and sustainable would be  Sigue leyendo

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

Take the panel with you

Solar Panels are getting cheaper every day, so this idea might convince you less today than it could have some time ago…

Anyway, suppose you have bought yourself one 300 W solar panel for your flat. In fact you found a smart orientation that covers your “base load” for the fridge and all the stand-by consumption and also lowers your consumption once you arrive home. It happens you have a e-bike that is prepared for you to plug your panel, for your daily commuting, keeping your battery fine or even charging while you are working. Additionally, you own an Electric Vehicle. During the week-ends, you can dock your panel for the journey and lower your consumption. And it happens that you are as wealthy as to have a second house in the forest, which is off-grid, so you use the battery of the Electric Vehicle for your consumption and you also plug your panel when you arrive.

Panel cycle

This is just an example of maximizing the asset utilization of a panel, for house self-consumption in two locations, and also for mobility. This will not be the case for most people, of course. Besides, regulatory frameworks may promote the use of the panel to feed the grid when it would be underused only for self-consumption and could be connected elsewhere for other purposes. Anyhow, the point of having portable generation opens more possibilities for generating one’s own energy, in this case at home and also for transportation. It is also an application for extending the access to electricity in developing countries.

In fact, if a person consumes (as it is the case in Spain) 3487 kWh/year of electricity and 9908 kWh of total energy at the home, together with 12000 km/year of driving, which can be calculated as 2400 kWh (with an EV doing 20 kWh/100 km) it makes a total of 12308 kWh. In order to source this with solar PV, he would need approximately 6 kW of solar panels working 2000 equivalent hours. These 20 solar panels he cannot take around with him that easily. For the moment…

P.S.: Allow me to include the crowded house video as the song I thought about while writing…

Hot. Classic. ConvertEV

The beauty of many classics is appreciated by almost anyone. Even a 5 year-old child has no problem admiring the lines of an old sportscar…


To keep these hot rides running, when the old engine is hardly repairable, there is an option; to make them electric.

There are at the moment some start-ups focused in EV conversion, as Zelectric motors, specialized in converting classics to electric, for example the VW Bug. Another example are the conversion kits from EV West, allowing individuals to convert the vehicles.

Here in Spain we have Jofemar’s Hidronew Project. And they have proven in EV competitions that their converted vehicles are fast.


Although with an electric drivetrain these models are more environmental friendly and have the old beauty and the new efficiency, it’s true that losing the original engine and noise is like tearing the soul of these cars. That’s why i’m in favor of converting the vehicles when the original engine can no longer be repaired as original.


As car workshops get used to EV maintenance and repair (simpler than internal combustion drivetrains) the conversions will grow, adding EV units by reusing old cars instead of building from scratch.

I’m sure this is going to get more and more common, converting an old car will get less expensive and it may become the cheapest (and coolest) way of owning an EV.

La única solución al déficit de tarifa y alguna propuesta más

Tras leer el útlimo post de Jorge Morales, estoy de acuerdo en que lo fundamental es proponer soluciones, no sólo criticar la mala política energética. Me animo a recoger algunas reflexiones personales que aunque no pretenden ahondar en todo, al menos me mojaré un poco proponiendo soluciones.

Un tema fundamental sobre el que hacer propuestas es en mi opinión el déficit de tarifa, pues es la preocupación política principal. Para resolverlo, opino que deben darse soluciones a la sostenibilidad actual del sistema sin utilizar parches injustos, retroactivos o indiscriminados. En esto supongo que estamos todos de acuerdo, incluso los que los han utilizado, pues no los consideran como tales.

Realmente hay varias soluciones, muchas serían también atajos injustos, que incluso pueden defender partidos de moda ahora, por ejemplo, expropiar las nucleares e hidroeléctricas, o las redes de distribución, nacionalizándolas por el “bien común” (Es curioso que expropiación suena tan fuerte como sonaba legislación retroactiva hasta hace poco…), multar a las grandes compañías con un importe equivalente al déficit de tarifa por prácticas oligopolísticas…  Por otro lado, opciones como subir el precio, hasta donde sea necesario (que además es la palanca mas potente para fomentar la eficiencia energética), no las defenderá ningún partido. Voy a defender aquí la única opción que yo veo (querido lector, si tiene una solución mejor, por favor responda a este post)

Si el consumo eléctrico creciera lo suficiente, se podrían cubrir los costes del sistema con los precios actuales, verdad? 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…

Sigue leyendo