Dear Ann,

With renewable energies in quantity, we run the risk of the collapse of the electricity grid.

With my best regards

Prof. Bachir ACHOUR

Dear Ann

A very interesting question and for me at least, something that I never thought about. Thank you for proposing it..

In first place it would be necessary to determine the source of renewable energy. If it is sun energy that requires large plots of land, that can be alternatively used for agriculture or cattle rising, then, an excess of photovoltaic or solar dishes can be detrimental from the land use concept, because it would be idle land.

If it is wind energy, that restriction does not exist since cattle can be raised and crops cultivated together with the wind turbines operation.

If it is hydro dams, it could be detrimental because the flooding of pastures and forests.If there is excess of energy it can be easily controlled by stopping some turbines and / or discharging more water using the floodgates and then bypassing the turbines

If it is small hydro I don't see any problem since they can be always bypassed.

If it is bio mass, the only inconvenience that I can see in from air contamination, but energy production can be regulated.

Regarding Prof. Achour explanation, I think it is rational.  However, more energy production means better life for people and affordable energy for industries.

I am interested in your question, perhaps you can elaborate a little more about how an excess of POTENTIAL renewable energy could be a problem

 Dear Ann, 

Follow onto and agreeing with both respected colleagues above, firstly can you please share some more details about that region in Philippines where you have excessive renewable energy?

Yes technically excessive renewable energy can have some issues but there are very easy and simple solutions you can adapt that convert these issues into tremendous opportunities.

In fact this is one of the most ideal situation for any region or country to have excessive renewable energy that will lead to great economy, healthy environment and human life and most importantly power!

Excessive renewable energy in any region can be controlled/ utilized in different ways to benefit the country including but not limited to;

1) Excessive renewable energy means, cheap energy, which could be utilized to develop all sorts of industry,

2) it can be diverted/ sold to other near by regions/ countries,

3) you can simply stop some of the energy production plants for some time, you don't have to produce energy/ run plants to their maximum capacity,

4) the energy price can be reduced further/made cheaper and people will get more benefit by developing small businesses or micro-industry, ultimately benefiting the country's economy,

5) even more ideally, government can give some incentives to people for new ideas/ products utilizing that excessive energy and that will bring tremendous opportunities for the people and country,

and many more solutions.

I have done a quick search on internet but could not fined that region you referred to.Please share more details about that region as it would be great to study how it has been made possible to achieve excessive renewable energy, as a scientist working in the renewable energy area.

Thanks, regards

Rehan    

Don't forget that the cost of the raw material used to generate solar PV electricity is zero, so the value of 'excess renewable energy' is simply what you can do with it. If you can't do anything at all with it, there is no cost involved in just switching it off!

However, the points raised by Dr Rehan are all very appropriate and I think well worth considering. I too would be interested to know which area you consider has excess renewable energy.

A situation arose like this in South Australia some months ago. Due to some  windy weather a lot of the transmission lines from the wind farms blew over (they must have been quite flimsy) and reduced the power supply to the state so much the entire grid shut down. So the wind farms were furiously generating, but had no customers at all. They too all had to shut down! Of course the fossil fuel lobby promptly blamed the renewable energy lobby - but even if the power stations had still been running they would be using the same transmission lines as the wind farms and would have been just as effectively disconnected. All goes to show you need a robust grid system when the source and use points of electricity are well separated.

Besides the previous answers the question one could raise is "what to do with the excess energy"? Particularly difficult in the Philippines case is where to export excess energy and how.

Storage solutions would improve usability of renewables. The advantage of non-renewables is simply you can turn them on whenever. Renewables do not always have this option built in.

Kind Regards

Roland

An interesting alternative to this problem is being researched in Germany and Denmark.

The concept consists in utilizing excess electrical energy to drive an electrolysis plant, producing hydrogen and oxygen. Hydrogen can then be fed to a biological reactor, mixing it with a stream of carbon dioxide. The mix of hydrogen and carbon dioxide gas can be transformed into methane by methanogenic archea. The methane can then be fed into an existing gas grid for household consumption.

This technique has the advantages of utilising a GHG as feedstock, making use of an existing assets, such as gas grid, and displacing a fossil fuel.

Whether this solution fits this particular case in the Philippines, I wouldn't know.

Dear Stefano

Thank you for a very  useful information

Dear Rehan,

The region I was talking about was Negros. I came across it from our local news channel. Here's the link: http://news.abs-cbn.com/video/business/05/10/17/is-oversupply-of-renewable-energy-in-negros-a-problem ; However, the video attached is in Filipino.

Thanks all for your insights!

Dear Ann, 

Thanks very much for sharing the link, I will study this and get back to this very interesting and useful discussion, sharing my experience and learning from other experts in renewable energy field.

Thanks dear Stefano for sharing another very interesting but practical idea for utilizing the excessive energy in electrolysis plant. I would like to add another point to this idea that the benefits would not only be to generate H2 energy from electrolysis, but also for example MEC can be used for wastewater treatment, which means the excessive energy can be utilized to solve another major problem of any region/ country (since wastewater treatment plants are energy intensive processes). We have conducted a very nice preliminary study on the concept of treating KSA wastewater by MEC and estimated the surplus energy from this system (H2 energy) as well, see below (published in Applied Energy).

https://www.researchgate.net/publication/309883189_Microbial_electrolysis_cells_for_hydrogen_production_and_urban_wastewater_treatment_A_case_study_of_Saudi_Arabia

Thanks Dear Roland we agree with you, of course we need to discuss about another very practical solution to this issue, which is the energy storage technologies (which is again very hot and much needed area of the time).

Thanks Ann for starting this excellent discussion.

Please we would like the experts to comment on this question as that would be great learning not only for students/eraly career researchers but also for everyone, and who know we may develop a new concept here for further research.

All the best 

Rehan

Article Microbial electrolysis cells for hydrogen production and urb...

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