PV Gap

Priscilla Said:

what are some of the disadvantages shared by all renewable-energy sources such as solar cells and . . .?

We Answered:

Well, in some cases (like solar cells) the cost can be prohibitive. Retrofitting a house with enough solar energy to participate in a buy-back program can cost $35,000, which would mean (at the current pricing structure) a 20-year ROI. Most folks in the US move every 5-10 years, so you would never realize that "payoff".
In other cases, like biodiesel and ethanol, the distilling process can take almost as much energy to produce, overall, as it will harness. Sure, you get portability with the non-fossil liquid fuels, but the energy to make the stuff still has to come from somewhere else, and right now, that means coal, nuke, or oil power primarily (at least in the USA).
Other disadvantages include unreliability, slow recharge times, limited range, and limited performance when compared to fossil fuels. Even wind power (which is fairly cost-effective) is not terribly reliable, depending on a variable power supply (wind). If generation points were distributed more broadly around the country, there might be more reliable average generation, but a still day still means "no power."
There is no doubt that "renewable sources" are a possibility, but the state of the art right now is about at the "finger painting" level.

Vickie Said:

Making renewable energy sources stronger?

We Answered:

To many people think that we need massive projects to make a change its not true.

Think of it this way to save at least 20% less electricity around the home TODAY if you changed your lighting to CFLs and turned everything off standby - pretty simple.

Do a few other things around the home save another 30% without spending to much. After you have done that you have reduced your power bills by half and paid for your original investments

Its not in the future its now!

Doris Said:

What are the effects of renewable energy?

We Answered:

Socially speaking these renewable sources of energy will have little or no effect on our lives. We all will plug in and extract electricity from a wall jack just like we have for so many years. We will enter service stations and fill up.
Economically the pursuit of generating electricity from these sources is and will remain to be more expensive that using petroleum products. None of these technologies are cheap and easy to maintain. They are not very portable except by the use of batteries which are expensive and terribly destructive to the environment, much more than CO2, water and trace amounts of Nitrous Oxide and carbon monoxide that come from burning petroleum and coal. Batteries introduce huge quantities Sulfuric Acid, Lithium, Lead, etc into the environment that cause serious damage to life unlike CO2 which is metabolized safely and quickly into trees and other living matter with no ill effects. The primary waste from petroleum products are CO2 and H20. These are essential to life. Further more it is less expensive to use nuclear power to manufacture petroleum like products and electricity much more safely than than any of these other methods. Before you nay say, find out how much CO2 exists in the atmosphere and what greenhouses need do to increase the production of plant matter. Find out how many cubic feet of high level radioactive waste has been generated in the western world' generating electricity. We could do better by cleaning up the trace components from our exhaust.

Becky Said:

Are infrastructures fueled by renewable energy sources more resilient?

We Answered:

Since you're talking about infrastructure, I'm going to ignore the installations which are completely off-grid already.

Solar and wind are inherently variable power sources, so need some kind of grid to stabilize them. The kind of grid we have today goes down once the main generators go down, and any distributed sources like solar panels on somebody's house intentionally disconnect themselves automatically when that happens. A grid of the future could be architected to take advantage of the distributed generation, and it might be possible for just one neighborhood to stay up even if the electric company goes down, as long as there were enough houses there putting out enough. I envision that like bittorrent, if a single house is a pig, it could find itself isolated from the neighborhood power sources.