It seems that we are inevitable to give more importance to renewable energy. It is a proven fact that renewable resources are so interesting to implementation, but with a some economical justification. 

In my opinion, with more development in technology, we will have more effective energy equipment. 

There are already several similar questions here on RG that incited discussions between non-experts who based their opinion on prejudice, hearsay and gut-feeling. It would be nice to have a more informed discussion here. So my counter question is: On what research do you base your opinion? Please use citations.

I would agree that, for the time being we are still strongly dependant, and will be for some more time, from traditional energy generation from fossil fuels. Renewable energies are a growing and welcomed contribution, but not yet sufficient.

Dear Shadi

the context is very important. In Africa, many rural villagers and farmers who have been without power for decades would say that we most definately have reached significant goals. If you ask power producers who supply major urban areas in developed contries the the answer will be quite different. Developing countries and remote off grid locations could therefore be considered places that benefits more from renewable energy as this type of energy is inherently distrubuted and more widely available. 

FC

Yes, I believe that renewable energy is a viable energy! Technology has come a long way in the production, transmission and distribution of this form of energy. The high need of energy for electric heating and electric car, which can be solved by distributed generation, supports this positive development.

It is a fact that renewable energy plants are the ultimate solution to future power. But the discontinuous and partially unpredictable availability forces us to plan a backup of conventional power plants or some energy storage system at various levels. The grid failures occured several times in the state of Tamilnadu in India (where 44% of power is from Solar/wind plants) last year raises concerns regarding the reliability of future renewable energy based systems. The low density of renewable energy sources (Solar energy) further increases the financial investment. 

It seems that we are inevitable to give more importance to renewable energy. It is a proven fact that renewable resources are so interesting to implementation, but with a some economical justification. 

In my opinion, with more development in technology, we will have more effective energy equipment. 

Could you please cite a reference for the increasing trend in nuclear power plant constructions?

The World Nuclear Industry Status Report 2014 illustrate a clear trend of the declining share of nuclear energy in the world’s power production. It states: “The nuclear share in the world’s power generation declined steadily from a historic peak of 17.6 percent in 1996 to 10.8 percent in 2013.”

http://www.worldnuclearreport.org/IMG/pdf/201408msc-worldnuclearreport2014-lr-v4.pdf

The report alsoreports about the status of construction as follows:

"As one year earlier, fourteen countries are currently building nuclear power plants. With Belarus, a new country was added to the countries engaged in nuclear projects, while Taiwan has halted construction work at two units. As of July 2014, 67 reactors were under construction (one more than in July 2013) with a total capacity of 64 GW.

The average building time of the units under construction stands at 7 years. However:

• Eight reactors have been listed as “under construction” for more than 20 years, another for 12 years.

• At least 49 have encountered construction delays, most of them significant (several months to several years). For the first time, major delays—several months to over two years—have

been admitted on three quarters (21/28) of the construction projects in China.

• For the remaining 18 reactor units, either construction began within the past five years or the reactors have not yet reached projected start-up dates, making it difficult or impossible to assess whether they are on schedule or not.

• Two-thirds (43) of the units under construction are located in three countries: China, India and Russia.

The average construction time of the last 37 units that started up in nine countries since 2004 was 10 years with a large range from 3.8 to 36.3 years.

Twenty-eight years after the Chernobyl disaster, none of the next generation or so-called Generation III or III+ has entered service with construction projects in Finland and France many years behind schedule."

On the other hand, BNEF reported on 9 January 2015 that investments in renewable energy has increased by 16% to USD 310 billion in 2014.

According to the Frankfurt School - UNEP Collaborating Centre, the worldwide renewable power generation capacity (excluding large hydro) increased to 15% providing 9.2% of the total electricity. The little more than 100GW of new renewable power generation capacity represent about 48% of the total new power capacity worldwide.

http://fs-unep-centre.org/system/files/2015gtr.pdf

Last but not least (USD are of 2012):

The IEA’s 2014 Energy Technology Perspectives state that the total investment costs between 2011 and 2050 for achieving a low-carbon energy sector (2ºC scenario, 2DS) would be an additional UDS 44 trillion (EUR 33.8 trillion) compared to the business as usual scenario (6DS) with investment needs of UDS 118.4 trillion (EUR 91.1 trillion) [International Energy Agency, Energy Technology Perspectives 2014, 376 pages, ISBN: 978-92-64-20800-1].

However, the estimated fuel savings of the low-carbon scenario are between USD 115 trillion (EUR 88.5 trillion) and USD 162 trillion (EUR 125 trillion) or 2.9 to 4.1 times the additional investment needed. This clearly indicates the huge societal benefit of a more aggressive climate change approach.

The power sector would require USD 39.6 trillion (EUR 30.5 trillion) for the 2DS and USD 30.5 trillion (EUR 23.5 trillion) for the 6DS scenario. The additional investments for the 2DS scenario compared to the business as usual would be USD 200 million (EUR 154 million) per year, which is less the current investment in the renewable energy sector.

A very interesting discussion. 

In the part of the world i live (Oceania), renewable energy is the only way some of our remote islands can get electricity. Solar and wind energy are favorites. As the research improves , the cost of energy ( i believe) will be lowered through improvments in that technology. There will soon a time when we will be able to tap into the vast ocean energy resource we have around the islands - and this depends onthe progress made in research on RE devices. Renewable energy is not only healthy for the planet - it breeds equality and promotes economic activity. And these are some of the islands that are worst hit with climate change effects. 

Coming back to the question - No renewable energy resources may not be as reliable as conventional sources yet - but as the trends highlighted clearly show, it does not matter. As research continues - RE  will  become more reliable. Many new RE technologies will surface in RE market and allow a mix of RE sources to slowly replace conventional sources. 

Mathematically speaking, fossil resources are finite and fall, and renewable resources are infinite, and have the advantage that they do not pollute.

Regardless of cost, humanity should strive for the widest possible use of renewable resources. The costs will decrease as industrial approach will increase.