<story><title>The Way Humans Get Electricity Is About to Change</title><url>http://www.bloomberg.com/news/articles/2015-06-23/the-way-humans-get-electricity-is-about-to-change-forever</url></story><parent_chain><item><author>cfsc</author><text>This article doesn&amp;#x27;t mention some serious problems that affect power grids reliant on renewable energies:&lt;p&gt;1 - The grids becomes vulnerable to the weather. There&amp;#x27;s no solar energy at night and it&amp;#x27;s greatly reduced in cloudy days. Wind power is unpredictable and closely matches the output of hydraulic power, so that the two sources can&amp;#x27;t complement each other. You can check Brazil in recent history to check the effects of droughts in the power grid.
In the end there is a need of conventional power plants always ready to backup the grid when the renewable energy is not available.&lt;p&gt;2 - The majority of losses of the power distribution network are on the last mile, when the voltage is lower and the current is higher. If every house and electric car become consumers and providers to the grid, most power movements occur in the low voltage networks. There&amp;#x27;s also the issue of batteries storing energy for later consumption. Lithium batteries have a 80%-90% efficiency storing energy.&lt;p&gt;3 - Since we are talking of the environment, rare earth metals have a very pollutant and energy intensive extraction process which in most cases is not accounted in the environmental cost of solar panels.&lt;p&gt;Replacing the majority of energy production by renewable energies will result in an net efficiency loss. I would rather support a balanced production with nuclear (fusion?) power plants providing the fixed needs of the grid and renewable energies making up the rest.</text></item></parent_chain><comment><author>SovietDissident</author><text>3 - The rare earth mining operations in China which provide the raw materials for solar panels, batteries, and many other electronics products are reportedly quite filthy and require massive energy (diesel trucks, processing plants, etc.)
&lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;www.theguardian.com&amp;#x2F;sustainable-business&amp;#x2F;rare-earth-mining-china-social-environmental-costs&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;www.theguardian.com&amp;#x2F;sustainable-business&amp;#x2F;rare-earth-m...&lt;/a&gt;&lt;p&gt;The push for renewable energy would not be possible at its current scale if it weren&amp;#x27;t so attractive to the political elite  (and subsidized as well), for the shortcomings you mentioned.  Fossil fuels and nuclear simply better fulfill the role of consistent, cheap, plentiful energy.  Unfortunately, even though nuclear is quite safe, has very few emissions, and emits a ton of energy, it takes a Herculean effort to get federal approval to build a plant.</text></comment>
<story><title>The Way Humans Get Electricity Is About to Change</title><url>http://www.bloomberg.com/news/articles/2015-06-23/the-way-humans-get-electricity-is-about-to-change-forever</url></story><parent_chain><item><author>cfsc</author><text>This article doesn&amp;#x27;t mention some serious problems that affect power grids reliant on renewable energies:&lt;p&gt;1 - The grids becomes vulnerable to the weather. There&amp;#x27;s no solar energy at night and it&amp;#x27;s greatly reduced in cloudy days. Wind power is unpredictable and closely matches the output of hydraulic power, so that the two sources can&amp;#x27;t complement each other. You can check Brazil in recent history to check the effects of droughts in the power grid.
In the end there is a need of conventional power plants always ready to backup the grid when the renewable energy is not available.&lt;p&gt;2 - The majority of losses of the power distribution network are on the last mile, when the voltage is lower and the current is higher. If every house and electric car become consumers and providers to the grid, most power movements occur in the low voltage networks. There&amp;#x27;s also the issue of batteries storing energy for later consumption. Lithium batteries have a 80%-90% efficiency storing energy.&lt;p&gt;3 - Since we are talking of the environment, rare earth metals have a very pollutant and energy intensive extraction process which in most cases is not accounted in the environmental cost of solar panels.&lt;p&gt;Replacing the majority of energy production by renewable energies will result in an net efficiency loss. I would rather support a balanced production with nuclear (fusion?) power plants providing the fixed needs of the grid and renewable energies making up the rest.</text></item></parent_chain><comment><author>torgoguys</author><text>Re: 1-I support balanced development (yes, including nuclear, but I get why some don&amp;#x27;t like it), but solar is AWESOME to pair with central electric production. It actually HELPS out with this issue. Very hot, sunny days is when there is peak power consumption. It&amp;#x27;s also the peak of solar production and can help avoid utilities having to spin up the (very expensive) temporary peaker plants.&lt;p&gt;Re: 2-Again, depending on how you look at it, solar helps with this, at least for homeowner rooftop production. If I&amp;#x27;m producing my own electricity on-site, the utility company electricity never has to step-down voltages and move that last mile. I&amp;#x27;m not using it (or I&amp;#x27;m using less of it) so the energy coming from a central power plant never has to come down the &amp;quot;last mile&amp;quot; to me! Feeding back in is where you&amp;#x27;ve got a bit of a point, but it&amp;#x27;s not really worse than with central production. In general distributed generation is going to be vastly more efficient (from the perspective of line losses) than central generation. Also, why bring up batteries? You don&amp;#x27;t need batteries to produce solar. If you have extra power, most people are feeding it into the grid, not batteries.&lt;p&gt;Re: 3-Agreed. Creating the panels is in general a very energy intensive process (in ways unrelated to the rare earth components), not to be ignored. It takes time for an &amp;quot;energy payback&amp;quot; if you will, but it&amp;#x27;s there. And the panels are very long-lasting.</text></comment>