PV Gap

Dorothy Said:

Going Green Tips?

We Answered:

Wow, Geothermal. Quite ambitious and I expect expensive.

Solar isn't cheap, either.

If you replace your AC with one that has a SEER rating of 14+, there is a tax credit. FYI Puron (R-410a) is much more efficient than R-22 or Freon.

Have you updated your insulation? What about your windows, as there is a lot of heat loss there. We ditched some of our mini blinds and replaced them with double honeycomb cloth shades. Coupled with heavier curtians, we have noticed a significant reduction in heat gain/loss.

You might also replace the weatherstipping at the doors and windows.

Gina Said:

Solar power for hot water use, worth installing?

We Answered:

There is some confusion when we refer to "Solar panels" and even some who operate commercial installations may not be aware that "Solar panels" can be Photovoltaic panels that produce electricity and Solar thermal panels used to capture heat. While photovoltaic panels are more costly they are at best around 24% installed. Solar thermal panels are cheaper and may be up to 80% efficient. It makes no sense to use photovoltaic panels to heat your home.

The numbers you give suggests a potential 2 to 21/2 year payback period on your investment. Most would consider this very worthwhile.

Solar thermal panels are part of an active system and can be designed to produce hot air or hot water. In general the hotter your base operating system is the more likely is loss due to outside temperatures. Solar thermal flat panels are cheaper but radiate some heat back into the environment which lessons efficiency but gives an advantage in environments with a heavy frost or snow load. Solar thermal vacuum tube collectors are better suited to higher system temperatures, cloudy days, and higher extremes in ambient temperatures. Some systems will mix both types of collectors with the vacuum tube collectors in series after the flat panels.1

I envy your choices. Radiant heating is the ideal distribution system for a solar heated system. It is ideal because it uses a lower distribution heat which may not be much hotter than your standard domestic hot water temperatures of about 120 deg F. As a good portion of any heating system is the distribution system you will have some savings in money there. If you had access to a pond or stream I would encourage you to examine geothermal heating as this is another system that works well with radiant heating and the water source makes it very economical.

The main difference between your present system and a solar heated system is the type of energy storage. Propane is a fuel that stores energy. A solar heated system requires some energy storage and this is usually in the form of an insulated tank of hot water. Sizing the tank and the panels relatively to your heating demands is very important. The tank can be reduced in size using a slurry of phase change materials but this is generally considered more trouble than it is worth. The tank is normally pressurized to equal your domestic water pressures but it would also essentially be an atmospheric pressure insulated "pond."

Systems that attempt to provide more than about 80% of the demand might include a ground loop. This is a loop in the Earth used to keep the solar panels from getting too hot in the summer. It may also be possible to generate electricity with excess thermal energy.2

It is possible to air condition using solar thermal panels but the system is an absorption system not the typical electrical/compressor/refrigerant system that is common elsewhere today. It is not practical to simply cool the house using the same radiant distribution system as condensation can be an issue so some form of separate air handling is generally required. I have provided a sampling of material to digest below.

Katie Said:

How can I get green power for my home?

We Answered:

I tried looking for the same thing a while ago without much luck. However, there is an alternative:

Companies are emerging that will allow you to lease solar panels for your house. They determine the cost by taking the average of what you normally would pay to an electric company.

Just Google "rent solar panel" and you can take a look among several companies that lease solar panels.

Sorry, I wish I could give you a recommendation, but at present I rent an apartment and do not have this option. Good luck, though!

Ben Said:

What is the best electricity generator for my scenario?

We Answered:

A fuel powered combustion generator is most cost efficient. You can get gasoline powered generators for under $150 per 1000W, which would do that.

Solar and/or a small wind turbine would be next up. You would need a battery set to store the charge, and an inverter to power your AC loads. Your computer, TV, and radio could be set up to work off of battery directly, if you choose the right ones.

Unless you are going to build a dam an all that, collecting energy from flowing water is not economical.

In any case, get a propane stove and dry your clothes on a line. You should get a tri-fuel fridge, if not a 12/120V one.

Sean Said:

so i wont to by a little camp in bingham maine and i wont to get solar power but i dont no what i should geT?

We Answered:

Depends on what you want to power with the system. We sell small packages that have the solar panels, batteries, inverter, pretty much everything you need for a cabin system (except some of the wire inside). http://store.altestore.com/Kits-and-Pack…

To decide which package you need, you have to determine how much power you need to make. You can go to a loads list calculator and put in what you'll be powering and for how long (one TV for 4 hours, two 13W CFL lights for 3 hours, etc.) and it will help figure out how many watt hours (Wh) you need. Then you can go to the off-grid calculator, and it will tell you how many solar panels and batteries you need. http://store.altestore.com/calculators/o…

Or call us with your loads list and we can help you figure it out.

http://store.altestore.com/calculators/l…