Parts 1 and 2 of this article considered eight advantages of solar power that contribute to home life and eight advantages of solar power in portable applications.

The advantages and disadvantages of solar power may seem to be poles apart, but are they? Would the advantages and disadvantages of solar power, placed on a balance scale, be fairly equal or not?

This final segment of the article will look at disadvantages of solar power.

Disadvantages of Solar Power

Talk to a dozen people who are considering it, and you may hear a dozen different lists of advantages and disadvantages of solar power. Those lists may be based on economic factors, weather factors, or convenience. The list we present here includes five of the disadvantages you will want to consider.

1. Cost: Initial start-up cost of solar power is considerable. While a single solar panel that gives emergency back-up energy is reasonable, providing an entire photovoltaic cell array to power your home will cost thousands of dollars. This is an initial disadvantage, but when consideration is given to the years of maintenance-free solar power expected, the cost is rapidly defrayed. Government rebates, tax credits, and other incentives can cut initial costs. Sell excess energy to the power grid to further recoup initial solar power outlay.

2. Climate: Many are of the opinion that solar power is only realistic for those who live in the world’s sunniest, hottest climates. While it is true that these climates have a great advantage in solar power usage, climates with cloudier, cooler skies can also use solar power. Germany is proving this true. See our article: Solar Energy - What Countries Use It?

3. Cloudy Days: Are clouds a disadvantage of solar power? They can be. Solar power reaches a PV system as sunlight strikes the panels. Cloudy days are, therefore, not the best for generating electricity. Our article, Solar Panels - What Country Uses the Most? shows, however, that cloudy days need not be a disadvantage. Even when the sky is mostly cloudy, any sunlight breaking through will bounce off the bottoms of the clouds. This can actually give more solar power than a cloudless sky.

4. Storage: For some, the task of storing solar power is a disadvantage. To remain independent of the power grid, you need battery storage that will provide power during dark hours. Such batteries are readily available, however, and do not consume a huge amount of space. If you decide to remain tied into the grid, batteries are not needed. Your photovoltaic (PV) System will supply electricity to your home during the day. Any extra solar power electricity can be exported to the grid. At night, the grid meets remaining needs.

5. Space: PV solar power panels require space. Home systems can require the entire roof. Many find this unattractive, but they do not want to clutter their land with solar power panels. This disadvantage is being addressed with new products such as PV panels designed to blend into the roof. Modern PV panels supply more solar power with fewer panels, too, since efficiency has been increased.

Conclusion

Having looked at these advantages and disadvantages of solar power, we hope you will consider it only a beginning. Most things present disadvantages with advantages, but one will usually outweigh the other. We believe solar power is worth serious consideration.

Solar power homes. Do they fill the need for free, clean, renewable, and eco- friendly energy?

They cannot fill the need for FREE energy, despite statements to that effect. Initial costs of solar power homes are too steep for the bank accounts of many. Once the photovoltaic (PV) panels and other elements of a solar home are installed, of course, the sunlight itself is free. But how many years will it take to recoup that initial investment? Will solar homes someday be within the scope of reality for everyone?

Solar Power Homes’ Initial Cost

The initial cost of solar power homes depends on a number of factors. How large is the solar home? Is the solar home being purpose built to that end, or is it being converted to a solar home? Is the landscaping oriented to solar power? Is the solar home to be in a good “solar” climate?

A house that is purpose built to be a solar home will initially cost a little more than a conventionally built house. The cost will be affected by your decision to have the solar home tied to the grid or off the grid. The list below is not all-inclusive, but gives an idea of items needed.

* Photovoltaic (PV) Panel System: Size of the system depends on your usage. An average, 3,000 watt grid-tie system we priced cost about $20,000 for everything - before installation. A 1080 watt off grid system for an average solar home was offered at $10,000 complete, before installation.

* Solar Water Heater System: A system to preheat water going into a standard water heater will cost about $3000 for the same solar home.

* Trombe Wall: Composed of masonry, this solar home wall is covered on the outside with glazing. Sunlight passes through the glazing, generating heat. The heat is conducted through the wall into the solar home for heating, out of the solar home for cooling. Costs will depend on size of wall, masonry, glazing, and labor.

* Solar Sun Room: This large room on the south-facing (in the northern hemisphere) side of the solar home has large expanses of un-shaded vertical glass to collect solar energy. The collected heat is stored or passed into the remainder of the house for winter heating. This means your solar home must have a large “extra” room that a conventional house would not have.

* Fluorescent Light: A solar home will not use conventional incandescent light bulbs. More costly compact fluorescent light bulbs will reduce the amount of solar energy needed.

* Appliances/Electronics: When selecting appliances and electronics for the solar home, you select energy-efficient over those that offer more “bells and whistles”. You select propane or natural gas appliances over electric.

A good place to begin if you are having a solar power home built ground up on your site is to choose a builder who is committed to building 100% ENERGY STAR qualified homes. Such homes are energy-efficient inside and out. The initial investment will be more than a conventional home, as already noted. The on-going savings, however, can be passed down to future generations.

Grants for building solar powered homes in the U.S. come in various forms. You will want to check all of the possibilities on local, state, and federal levels. A federal tax credit is available for solar homes in all states.

Database of State Incentives for Renewables and Efficiency (DSIRE)

A great database, DSIRE offers information on various incentives, rebates, and grants for building solar powered homes. Government programs as well as corporate programs are listed and explained.

For example, here are just a few of the incentives, rebates, credits, and grants for building solar homes in Montana.

1. A state loan program will lend up to $40,000 for solar home elements such as solar water heat, photovoltaic (PV) panels. The solar home owner has 10 years to repay the loan, at 5% interest (2006).

2. Energy West of Montana will lend up to $2000 interest free for solar home energy efficiency measures.

3. Northwest Solar Cooperative will purchase extra electricity from solar homes that are tied to the grid at the rate of $0.05/kWh through December 31, 2009.

4. NorthWestern Energy - USB Renewable Energy Fund periodically gives grants for building solar powered homes. For solar home PV installation, incentives of $3.50 per watt are offered. The maximum per customer is $7,000.

5. Montana has a property tax exemption for solar homes using passive solar space heat, photovoltaics (PV) panels, solar space heat, solar thermal electric, solar thermal process heat, or solar water heat. The 100% exemption is valid for 10 years after building the solar home.

6. A personal tax credit of $500 is allowed owners of solar homes that use passive solar space heat, photovoltaic (PV) panels, solar space heat, or solar water heat.

7. A net-metering law permits investor-owned utilities’ customers to net meter systems that generate electricity using solar up to 50 kilowatts (kW).

In addition to such grants, rebates, and incentives, database programs also reward installation of energy efficient appliances, weather stripping, and other energy-saving measures.