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

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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

Asset utilization Vs Energy transition

Collaborative economy, also called the sharing economy, is growing, and it can be understood as a synonym for resource efficiency and increased asset utilization. It also allows the energy transition. How? An example; car sharing, offers increased asset utilization of the vehicles and fosters the energy transition with more sustainable mobility.

In the energy sector, and in the case of utilities, this is not very common, but let’s try to look at some trends;

For example, grid interconnections, as proposed with the EU Energy Union policy, is part of a more collaborative economy. It means the sharing of power capacity and available renewable resources in an extended market. Of course it is not peer-to-peer, but instead “grid-to-grid”. Interconnections improve asset utilization (of the most competitive assets at least, as well as avoiding investments in peaking capacity) and also help toward the energy transition as abundant renewable power can be exchanged between countries.

Image by Gabriel Schouten de Jel

Image by Gabriel Schouten de Jel on freeimages.com

For Spain, with high generation overcapacity, to increase interconnections is key to making use of existing power capacity and avoiding wind spilling, for example.

However, there is another example of improved asset utilization where there is a conflict with the energy transition…

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…

DG extends asset life – PV Grid

The results from PV Grid study initial report were presented in Madrid this week (organized on the 3rd July by @UNEFotvoltaica) and there was some interesting discussion on Solar PV integration.

One of the issues presented by the distributors (Enel, Fenosa and Iberdrola) were the inverted power flows in substations and the difficulties to control voltage when distributed PV reaches certain penetration. This was specially the case for Enel Distribution, as they presented an example in Puglia of reverted power flow from +10 MW to -30 MW, consequence of distributed solar. In my opinion, although having much more distributed PV than spanish distributors (15,9 GW Vs 4,3 GW), was not as “worried”.

The issue I want to highlight here is actually the increase in PV penetration in distribution has the effect of reducing the load of distribution transformers, specially in the hottest moments, therefore reducing insulaton degradation (see IEC Thermal index and halving interval in IEC 60216). This can actually increase the life of these assets, benefitting the distribution company.

PV protecting trafo

It’s true that when power flows become reversed, and higher than normal consumption load, the effect is reduced lifetime, but up to this “reverted-equivalent-load” point it is of interest to the distributor to have additional distributed generation. Moreover, where losses influence the distributor’s regulated income, having enough PV to reach a load-consumption zero-sum as much time as possible during the day is in it’s economic interest (as in the following graph).

Load change with DG increase

In my opinion, distributors should set distributed generation targets per area in order to reduce their substation loads and increase their assets lifetime. Not too much intelligence (no smart grid hard/software)  is required to manage this, just setting the best case generation in the distribution, and promoting/accepting connection points up to the most appropriate to their network.