Dear Robert

You are right. Many countries in Europe did great in the past years in new energy (wind, solar, Etc.), but it became for example about 20% of total demands during the past 15 years in Italy.

The analysis show that, the consumption of energy and for example natural gas decreased in Europe from 2005 to 2014 not because of using new energy plants, but particularly because of the economic and financial crisis. It means that after passing the financial crisis, the energy consumption will be rise again and the prediction by World Energy Council show that the energy demands in Europe will rise about 70% by 2030. Therefore, for generating the new required energy by electric cars the current trend of developing new energy plants must be at least triple to fulfill the new demand. If not, more fossil fuel plants or nuclear plants will be needed. In fact in all of the scenarios for energy in the future besides increasing the renewable energy, new nuclear power plants are assumed to be built specially in UK and France.

The problem with arid countries is worst. The International Energy Agency estimates that desalination in the Gulf represents approximately 12 per cent of the region’s total energy use. Saudi Arabia alone burns 1.5m barrels of oil every day to desalinate water. This huge amount of fossil fuel in the desalination plant will produce Co2. Therefore, if the energy demands rise by electric cars, more water and fossil fuel in power plants will needed since the use of new energy in these countries is not as much as Europe.

My main focus is water consumption and I must consider that, produce of any devices and even the aluminum frame of the solar panels will used water and energy. My other point is that, if it is possible to use electric vehicles and increase the water consumption and withdrawal in the power plants in the countries that are producing water by desalination plants.

In conclusion, both cases might results in more pressure on water resource (that is not possible in some countries) and more production of Co2.

Thank you

Your assumption that electric cars will run on traditional power-plant produced electricity should be improved.

1. Calculate the change in power use in the entire transition period of the shift. There are other positive and negative impacts on the energy need in this 15-30 years period.

2. Consider the change in energy systems from centralized to decentralized and from fossil and nuclear to wind and solar in the same period.

3. Calculate the largest increases in water consumption during the period to explore the riskiest years. My gut reaction is that the water use for power production will decrease globally and in the developed countries.

4. Apply rational spatial resolution. While the water consumption for electricity consumption will decrease in the developed countries, in developing countries it can be different. Also, the available water sources are different.

Currently, a shift is happening from fossil and nuclear energy to wind and solar energy. Electric cars perfectly compatible with the photo voltaic systems, they can be charged during the cheap power period and they can sell electricity from their batteries in the peak periods if they are out of use.

Middle East ensures the best return on photo voltaic due to the high energy availability and density from sunlight (the payback period is available by states in the US in the Internet, the correlation between available sunlight and the faster return is obvious -less solar panel you need to buy for the same production).

Apparently, the change from fossil to renewable power is way faster than the change from fossil cars to electric cars (electric car consumption increase is not measurable yet, but 30% of the power already produced from renewable sources in Germany). Without renewable energy the electric cars do not make to much sense, maybe they could reduce local pollution in an urban area. By using renewable energy, electric cars are really useful.

Dear Robert

You are right. Many countries in Europe did great in the past years in new energy (wind, solar, Etc.), but it became for example about 20% of total demands during the past 15 years in Italy.

The analysis show that, the consumption of energy and for example natural gas decreased in Europe from 2005 to 2014 not because of using new energy plants, but particularly because of the economic and financial crisis. It means that after passing the financial crisis, the energy consumption will be rise again and the prediction by World Energy Council show that the energy demands in Europe will rise about 70% by 2030. Therefore, for generating the new required energy by electric cars the current trend of developing new energy plants must be at least triple to fulfill the new demand. If not, more fossil fuel plants or nuclear plants will be needed. In fact in all of the scenarios for energy in the future besides increasing the renewable energy, new nuclear power plants are assumed to be built specially in UK and France.

The problem with arid countries is worst. The International Energy Agency estimates that desalination in the Gulf represents approximately 12 per cent of the region’s total energy use. Saudi Arabia alone burns 1.5m barrels of oil every day to desalinate water. This huge amount of fossil fuel in the desalination plant will produce Co2. Therefore, if the energy demands rise by electric cars, more water and fossil fuel in power plants will needed since the use of new energy in these countries is not as much as Europe.

My main focus is water consumption and I must consider that, produce of any devices and even the aluminum frame of the solar panels will used water and energy. My other point is that, if it is possible to use electric vehicles and increase the water consumption and withdrawal in the power plants in the countries that are producing water by desalination plants.

In conclusion, both cases might results in more pressure on water resource (that is not possible in some countries) and more production of Co2.

Thank you

The crises is over by 9 years and electricity consumption not increased but decreased and 25% is from renewable in the EU. Look at the graph, three years after the deepest point of the economic crises, in 2011, the consumption bounced back and was the highest ever. After 2011, the total electricity consumption is decreased.

http://ec.europa.eu/eurostat/statistics-explained/index.php/Electricity_production,_consumption_and_market_overview

Although we disagree in that, this is not my point especially not about the forecast differences - I cannot see the future better.

My point is, the change in the total power consumption (electric cars are only one element) and the change in electric systems (decentralized) and sources (solar and wind) should be considered to analyze the effect on water consumption.

It means you need to investigate the entire study period from energy need and production perspective year by year to know when you have an additional water need and what is the necessary volume. To put electric cars in this context would level up the value of the study. I offer my contribution if you want to write another paper considering all of these phenomena.

I agree that the study region is important. It looks the energy need from fossil or nuclear will decrease in developed countries, maybe developing countries are different. Also, the available water sources are different by geographical region.

Dear Robert

Thank you for your analysis. You are right and adding the elements might change the results such as new type of electric systems (decentralized) as you mentioned and I hope so.

I certainly accept your contribution for adding new parameters to the analysis as you described.

Best Regards

Pirouz

As you are aware, electricity does not come from hydro-sources sources. we have other sources. If we use renewable sources to generate electricity, how does that affect the water balance; if we tapped the sun as the sources of electricity, where does water usage come into the equation? It is better to divulge into the issue with a broad mind -the mind of a policy maker, and not one of a specialist with a narrow view.

Dear Prof. Mwaguni

I am totally agree with you about your sentence "one of a specialist with a narrow view". If all problems become solve with a team of professionals there will be no problem such as water crisis in Middle East, Energy Crisis or Water Pollution in India and China and Etc.

According to your question about "Where does water usage come into the equation? "

1- Do you think it will be possible to produce about 40% of energy in India with renewable energy by 2030? This is even more than doubled of "Paris meeting" in 2016.

2- Producing the new energy device will also use water.

We must also take into consideration that the production of renewable energy such as solar PVs and even the aluminium frame of it will use many water in mining. You can check why Withdrawal per capita in Australia is 5,104 m3/y (first in the world) and 690 m3/y in India. Do you the countries have enough water for production of EVs and New Energy devices? Saudi Arabia alone burns 1.5m barrels of oil every day to desalinate water. The same trend exist in Kuwait and Etc.

The analysis about the EVs is based of the power generation in the worlds and as i mentioned if we continue with the same trend there will be water problem.

The analysis for India based on BP Statistical Review of World Energy (http://www.bp.com/statisticalreview)

2016: Total= 723.9

Oil: 212.7

Natural gas: 45.1

Coal: 411.9

Nuclear Energy: 8.6

Hydro electric: 29.1

Renewables : 16.5

I hope the problem become solve by a team of professionals since I am just one researcher with one team in a university in Italy.

Best Regards

Pirouz

I am an optimist. I am confident that as we move on, other ways of producing electricity shall be found. And while it is true that many productive activities need water, science has shown that we are moving away from batch production to real time production, minimizing the use of most materials required, we shall get there even in our search for new forms of electrical energy.

interesting question

good luck

I would like to add 3 consideration:

1) the penetration of RES in electricity production, at least in Europe, is increasing. In Italy the 37% of the elcectricity is produced by renewable (see the statistic of TERNA, the national TSO)

2) The price of the PV technologies is going down while the efficieny is growing. It is estimated that the new PV technologies will have an EPBT lower than 1 year (in suother EU, so immagine in Oman or Saudi Arabia). This will result in a further increas in PV penetration

3) EVs thank to their battery can be seen as energy storage. Hence they can help the penetration of non - programmable RES (like solar and wind) giving and higher grid hosting capacity, especially in a V2G scenario.

Dear Girardi

Of course you are right about the electrical point of view. My analysis was based on the water resource management and the correlation of water and energy in different regions since have been forgotten in previous studies. I also hope to see better trend and more analysis about the sustainability of renewable energy with consideration of water resource in all countries.

I mean that, my concern is not just the necessity for increasing the efficiency of PV technologies, EVs and other power generation technologies, but also we must take into consideration that, the generation of these new power demands and even the production of these devices will also use water and energy from mining to factory.

Here is a part of another studies just about air conditioners:

"By 2030, in India alone there are expected to be an additional 112 million AC units (up from just 4 million in 2010) consuming 150 gigawatts of energy, which is equivalent to 300 new power plants."

(https://www.theclimategroup.org/news/solving-air-conditioning-paradox-dan-hamza-goodacre-climateworks)

Finally, production of 37% of the electricity while the total energy consumption did not changed too much might be depends on other factors. What if the total energy consumption increase about 70% in 2030 (by EVs, by increase of using air conditioners because of increase of temperature and Etc.). In this case the new energy share in Italy will be the same as 37% in 2030. I hope so. But if not what will happen to water resource? The consequences for arid regions might be worst.

Best Regards

Pirouz