A long story made short as:

No country can run entirely on renewable energy- primarily because of the limitations of  natural resources /raw materials/ financial resources/technical knowhow  constraints.The  table attached along with gives, very briefly, Ten renewable energy sources  and the appximate % of electricity produced in some countries of the world

Thank you Sir Manohar Sehgal, for sharing such a valuable information

Hi Rasit,

Whether it is a country or a province, I guess it depends largely on the energy demand and the capacity that available renewable resources add up to. (By the way for both, I am referring to strictly values on ground ! That is, energy demand for avenues like air travel or seafaring are not included.)

In India, we have a small province by the name of Sikkim, that is almost entirely supported by small hydro stations, if that can be taken as an example. Being a border province, there is a considerable defence related activity which, by the way, use diesel support. The civilian consumption is largely supported by small hydro.

But then like I said, SIkkim is a province with very little industrialisation, so demand is low. Further, it is a mountainous state, so a good quantity of hydro resources can be relied on. Works out to the same demand and supply consideration that I started with.

Cheers !

-Sanjay 

Very recently there was a article named

Portugal Runs Entirely On Renewable Energy For 107 Hours: Other Countries On Clean Energy 

another one named

Costa Rica Is Now Running On 100% Renewable Electricity

Mohamed,

That I understand is stale news now, largely established as being inaccurate !!

-Sanjay

Yes, it is possible to run a country electricity need entirely on renewable but needs huge investments and research.  

From a system stability perspective, I think certainly not , As the conventional generators has the ability to supply some amount of energy stored in its rotor during critical conditions which is extremely crucial! The grids with renewable systems may need huge energy storage which may be extremely costly to achieve the same purpose!

Dear Ata,

So important question or may be considered as a reminder. I think that the exact answer is YES, besides all developed countries will be run entirely on renewable energy.

All the best, Emad

I heard that Denmark plans to run entirely on renewable energy by 2050. However, with present technologies it may be not sustainable. The supply of solar and wind power in heterogeneous over time, and one needs a lot of hydro power to balance it. Denmark can find it in Scandinavia, but it will be not a full independence. As soon as cheap batteries will appear, one can think about such independence. It is also an economic issue whether it is optimal economically. At present, renewable energy needs subsidy.

Yes, It is possible. For my best of Knowledge, for one day, Germany perhaps do the same by using solar energy. Another renewable energy is there H2 energy.

Norway is mostly hydro. Interestingly, the past three years, we are seeing more news reports of European countries being periodically supplied with 100% renewables (i.e. wind) without disrupting the stability of the network.

For the engineers in the conversation, I wonder if this is disproving the idea that the more renewables the system carries, the more unstable the system becomes?

Hi Ricardo,

In the "conventional sense", what you say about Norway is very true. But isn't there a new configuration for nuclear power generation that the nation has been working towards ?

Any idea about what stage of development their nuclear energy project is in ?

With best wishes.

-Sanjay

I am convinced that, with today's technology, it is possible to run a society entirely on renewable energy, with the exception of fast and massive air transportation. 

Mankind should anyway, in a century or two (and preferably earlier because of  the risks linked to climate change), run entirely on renewables, as we did three centuries ago but with a much better comfort!

It depends upon geographic location of the country.

[1]I had surveyed the literature up to 2011 in my first answer .  But I submit before the wisdom of my worthy colleague for his voting me down. Hope my friend/s would take a view on my country- India. Here  I  will discuss ONLY the approximate cost of conrsuction of nuclear plants that India will need to bear  wrt to its economy  

[2] But  I have intentionally left  other contraints like Operating costs which include:

 Fuel cost= 28% (2013), Waste disposal costs, Decommissioning,

Proliferation and terrorism , Safety, security and accidents,

Insurance.

 [3] Pls. go through the literature as we are primarily here for an academic discussion.

[4] Yes;  as rightly said by respected Dr Claude-Alain Roulet  ; if you can wait  for more than half a centuty or so then  quite a number of countries especially small/ advanced [Costa Rica= 4864958; area= 51100 sq Km); Israel=852000; area=22072 sq Km]  countries may make it.  India ( population= 1329358296; area= 32 87590) will need  more than half a century. Again, pls note  that Delhi- India’s capital has population   appxo 1.5 times the whole of Israel and three times the whole of Costa Rica. We make 19% of world population

[5] Since most of us are science students, you are requested to put forth some reported data from the literature in support of your answer. Our wishful thinking will not carry weight.

  WRT to India

[a]The construction cost estimates for new nuclear power plants are very uncertain and have increased significantly in recent years. Companies that are planning new nuclear units are currently indicating that the total costs (including escalation and financing costs) will be in the range of $5,500/kW to $8,100/kW or between $6 billion and $9 billion for each 1,100 MW plant. Reported- click- Nuclear Power Plant Construction Costs- July,2008 for authentication

[b] Taking average=6+9/2= 7.5  $ billion  for One  1100MW Nuclear plant

 [c]Total electricity consumption in India [  Reported for 2011 - pls verify]

757.9 TWh  

757.9*1000000=757900000 MWh

 [4]   Suppose whole electricity is to be generated from nuclear energy( though there are 9 more renewable  sources), then  India needs= 757900000/ 1100=689000 nuclear plants; each of capacity 1100 MW.

[5] Total cost of construction for the plants India  needs=7.5* 689000=5167500  billion $=5167.5 trillion $

[6] But India's economy is 2.1 trillion dollars(2100 billion dollars) and  its budget in 2016 is around 295.522billion dollars[ All reported in literature]

[7]   I wait for your kind response

Rgds

As renewable energy I understand the transformation of energy agents that will be avaialable for milions of years (see attached paper and link). This is the case for solar energy and related such as hydro, biomass, wind, oceans thermal gradients, etc., assuming a reasonable average use of 2000 W/person. It is also the case for geothermal energy if used in a limited way. But, with todays technology, nuclear energy is not, in my opinion, renewable for two reasons: availableUranium is consumed pretty fast and this technology pèroduces unsustainable wastes. 

It is however not excluded that fusion energy could be, in a far future, considered as sustainable.

There are surely now some priviledged countries or states that produce all their electricity from renewable energy. Fore example, in Switzerland, the state of Valais exports more hydro-electric energy thant it uses. But they import oil and gaz for heating, because its cold winter climate. 

But my basic point is that mankind shall commute from today's non renewable energy sources towards only renewable ones, as soon as possible. 

Speaking about India, I am collaborating to a Indo-Swiss programm (BEEP) aiming to improve the energy efficiency of buildings (see second link). This has shown, among others, that the energy use of buildings can be strongly reduced and its comfort greatly improved by an adapted design.  A better use of the energy sources is a prerequisite to sustanability.

https://en.wikipedia.org/wiki/Renewable_energy#cite_note-2

http://www.beepindia.org/

 My young friends

 [1]  Thks. Dr laude-Alain Roulet.

 since your good self is the most informed  person about my country- the India.

[2] And per your previous answer  

“Mankind should anyway, in a century or two (and preferably earlier because of  the risks linked to climate change), run entirely on renewables”---------

[3]   I leave it for friends to  decide whether I deserved vote down  for my humble observation?

“No country can run entirely on renewable energy- primarily because of the limitations of  natural resources /raw materials/ financial resources/technical knowhow  constraints” ---.

[4] Let me humbly submit that as a teacher( who taught for over half a centry( 37 years+13 years after retirement)- I feel relieved  since the reality is that the time for total change over  to renewable sources of energy  is  appxo. One century( say 80 yrs) away  for India which  constitutes 19% of the world population.

[5] Again it is amply proved that that this Q&A format of Research Gate is  PRIMARILY  meant for an ACADEMIC DISCUSSION/ GIVING  RIGHT INFORMATION TO THE YOUNG SCHOLARS and not for simply vote up/ down.

[6] Lastly,  any one can  authenticate  the data given by me- be it the table in my first answer or the references cited in my second answer.

[7] I will delete  my   last two answers after a day.

Rgds 

Yes, it is certainly possible to supply electricity with a 100% renewable portfolio.

I would suggest you to check on the International Energy Agency website the statistics for Paraguay, which runs its electricity matrix based on 100% of hydropower.

On the other hand, 100% of renewables certainly brings more vulnerability to the country, usually represent higher costs and, often, increase in electricity imports. In this sense, it cannot be stated that every country should aim to become full renewable. In some cases, it could be interesting, but in many others not.

Yes, it is possible.

I have read several newspaper articles. I think, they said that "all of electricity generation of Germany (I think, in June), Denmark and Portugal was generated from renewable energy sources for a few hours or a weekend".

What are the parameters of the problem? Some key questions you must answer first include the following:

These are only some of the parameters of the problem one should provide before one can really answer such a question with any significant degree of confidence.

Portugal kept its lights on with renewable energy alone for four consecutive days last May.

https://www.theguardian.com/environment/2016/may/18/portugal-runs-for-four-days-straight-on-renewable-energy-alone

Yes, it is possible as Portugal did it based on Wind power for some days in 2015. 100% wind generation for supplying the demand.

I really wonder why a country might wish to run entirely on renewable energy, especially with the present state of renewable energy technologies. If the idea is to gain publicity, perform an experiment (i.e. for 107 h), etc., the answer to the posted question is "yes".

However, practically there are many challenges, for instance:

   - Any present energy technology, incl. renewable (wind, hydro, solar, combustion of renewables, etc.), harms more or less the environment. "Green", "environmentally friendly", etc. are rather advertising than technical terms, "ecologically compatible" seems to better reveal the fact that some technologies pollute within present specifications for air, water, soil, etc. quality.   

   - Sustainability is a delicate balance between production and preservation of environment. This balance is improving in absolute terms by evolution both of production technologies and pollution control technologies. Tilting this balance in either direction by revolutionary decisions seems at least dangerous;

  - The potential of the present renewable energy technologies to contribute to energy consumption is rather limited. Moreover, from a general engineering point of view, having a mix of energy sources, still provides better management options, which lead to using less energy and thus - to lower pollution,   

Thermodynamically, if you see the earth and its atmosphere as a system, the only energy that comes into this system is from sun. Remembering that energy can neither be created nor be destroyed answers that whatever fuel we have burnt till now is a derivative of solar energy. This could imply that using solar energy directly is a potential solution but the real question is how to make it economical so that everyone prefers it. The day someone answers this question will mark the starting of solar era and every country will run on it.

With respect to Dr. Rahman's point, there are basically two ways for solar and wind power to become more economical than coal and natural gas.  The first is for the price of former to decrease and the second is for the price of the latter to increase.  Coal is largely finished in developed countries by regulatory fiat, but this has decreased the cost of fuel in countries that still use it due to additional supply freed up.  Natural gas has of course enjoyed a plentiful supply in recent year and prices are also historically low.  However, arguably the fuel price for fossil-based generation does not include externalities like emissions impacts on local air quality and global climate.  If these costs were fully included, it is quite possible that renewables would be more economical than fossil-based generation. This is why countries many countries impose SOX/NOX regulations and some are now considering carbon taxes.

A second important point is that in fully competitive deregulated markets the marginal cost of renewables is effectively zero, while (simplistically viewed) fossil-based generation is priced as the fuel divided by plant efficiency plus operating and maintenance marginal costs.  Since sunk costs do not figure into the price of supply, renewables (once built) always get dispatched first (except where system reliability demand otherwise). As long as the marginal unit is fossil, the producer surplus for the renewable units is non-zero and renewable plants can recover their capital costs in the long run.  If however, there is only renewable generation, then the marginal cost is zero, and the price is therefore zero.  In this case the renewable generators cannot recover the capital costs and the system is no longer economically viable.  This irony is the basis of the revenue adequacy question and has lead some to think that the current preferred market design will not work in a future with 100% renewables.

Of course, Portugal is one of those, boasting 100 % or close to 100 % renewable. But, there are other issues that need to be dealt with. But, if a country is ready to deal with those issues, sure, it is entirely possible.

But, for most other countries, it will be extremely difficult, if not impossible, to rely just on renewable energy. It is just a wishful thinking....

Regards,

Jeremy