Solar Power for Houses: Your Residential Solar Power System

Green engineering positions typically want an undergraduate degree in engineering or closely related discipline, although a high school diploma with four years of technical and engineering experience may also be considered acceptable. There may also be guild requirements. Many of the engineering jobs are electrical, electronics, or IT positions.

Positions labeled as technician often don’t require a full degree and may be more accessible to those trying to enter the field. They often expect an Associate degree or several years of experience in the field. Engineering and technical positions aren’t open to high school graduates without experience in the field. Mechanics are a different story altogether, and often require a lot less training than engineers.

General Electric is currently hiring a lot of people for these positions. However, when working for energy companies it’s a good idea to check whether the particular projects you’ll be working on are actually green. If you’re working with coal, it is not a green job, even if you found it on a green energy jobs board.

There are a lot of ads for build-your-own solar panels on the internet, including on this site. I have no control over what ads do or do not appear, but felt a bit of research as to whether DIY solar panels were possible or cost effective was in order.

Solar Panel Price Comparisons

When sites say ‘build solar panels for under $100!’, they often seem to be comparing the materials cost of the homemade panel to the cost of an entire solar photovoltaic system which (for a house) usually includes multiple panels, an inverter, a charge controller and sometimes batteries. This is not comparing the same thing. A true cost comparison would be one of two things: the cost of the entire system, or the cost per watt of power produced by a single panel.

The full cost for a DIY solar photovoltaic system includes the number of panels that you wish to build as well as buying or building all the other parts of a system. Also include your time that you will be spending building the panels and mounting racks and then wiring and installing everything. A single solar panel by itself is not much use for home applications without an inverter and charge controller, and one solar panel will not power an ordinary house. Costs for solar panels are usually a little over 1/3 the price of an installed system, so while they are a major component they are not the only component.

Comparing Solar Panel Prices: Price Per Watt

The usual method of comparing the prices of solar panels is price per watt. For example, if a 60 watt panel is built for a materials cost of $104.85, as the maker of mdpub.com did, the price per watt is $1.75. The average price per watt for a commercially made module of over 125 W is $4.39 as of September 2009. Prices for smaller modules are generally higher per watt, so the home-made panel looks pretty good. So yes, it is possible to build a solar panel for less money than you would pay for commercial one. But there are several caveats:

• This is presuming no materials were ruined while you learned how to make the panel
• This is presuming that you manage to make the panel work properly
• This is counting your own labor cost as $0
• This is assuming the you do not have to buy soldering equipment or paint, plexiglass, wire, or screws in order to make the panel since the author of this site had them on hand
• The person who made the solar panel used as an example has also built a wind turbine and a jet engine

DIY Installation of Solar Photovoltaic Systems

Once you have made your panels, will you be installing and wiring everything yourself or will you get someone else to do it? The level of skill required is an important consideration because installing solar photovoltaic systems means working with electricity, which has a certain amount of inherent danger involved. On-grid residential solar power systems usually involve high-voltage electricity, which increases the danger if you do zap yourself.

So is Building Your Own Solar Panels For You?

I would not want to try this myself, nor do I have the equipment I would need. If you have to go and buy the equipment and then teach yourself how to use everything I would not advise attempting to do it yourself. If, on the other hand, you are an electrician with a large workshop looking for a project, building your own photovoltaic system might be worth another look.

Sources:

http://www.mdpub.com/SolarPanel/index.html

Cassandra Sweet. Sept 8, 2009 Let the Sun Shine. The Wall Street Journal

Solar module retail price environment Sept. 2009

Like all companies, green energy companies require people to organize all the work that’s being done. Someone to do the payroll, someone to hire people, someone to make sure people do the things that need to be done.

Requirements for administration and management positions in green energy are not very different from requirements for similar jobs in other industries. However, some experience with construction or renewable energy is usually preferred, and is required for some positions.

Check the requirements of the individual job you are applying for carefully. Requirements vary greatly between jobs. If it doesn’t say a certain type of experience is required, it probably isn’t. Don’t avoid applying because you assume a certain type of experience is required.

If you have any experience in construction or renewable energy, let them know. It could be the selling point that gets you the job. Experience in administration, management or customer service as related to the duties of the position should be emphasized, especially if you lack experience with green energy. Display the skills you have, and emphasize your willingness to learn those you lack.

In addition to jobs labeled as administrator, manager, or customer service specialist, there are a great many jobs in the solar industry that require managerial skills in addition to technical skills. For example, senior engineers are often required to do administrative tasks, and individuals with administration experience are preferred for these positions.

A few solar energy companies that hire for administration and management positions:

Borrego Solar

Conergy

Juwi Solar

SolarCity

or check out Green Energy Job Search Sites

Alternative Energy.com

Green energy jobs online

Renewable Energy World

Passive solar heating is a great way to provide much of your home’s heating for free. Almost every home gets some solar energy coming through the windows, but there is a vast difference between the average house and a home heated with passive solar energy.

Building a new house that is passively solar heated is not significantly more expensive than building a normal house. This makes passive solar the most cost-effective form of solar power for the new home. Every new home should be built using passive solar techniques because home heating and cooling needs can be reduced greatly – potentially to zero in certain circumstances.

All this sounds wonderful, but there is one caveat: you must find a good architect who understands passive solar design. Some architects do not understand how to do it properly and mistakes made during the building process may prove costly later.

Passive solar heating covers a wide range of strategies, including passive solar thermal hot water heaters such as the batch and thermosyphon, but it’s usually used to describe heating the house air and structure.

Direct Passive Solar Heating

The simplest form is direct passive solar heating. This involves big windows on the south side of the house. The sunlight falls onto a dark surface with a high heat storage capacity such as a masonry floor or wall painted a dark color. Water is sometimes used instead – this involves water contained in glass or transparent plastic. It has slightly different properties than solid walls, but the basic idea is the same. The wall or floor absorbs energy on sunny days, and releases it at night or on cloudy days when things get cooler.

Of course, you don’t want the house to overheat in the summer. This is generally avoided by building overhangs over the windows. In the winter the sun is at a low angle and comes in the window. In the summer, especially near midday, the sun strikes the overhang and doesn’t come into the room. This leaves the room much cooler.

Trombe Walls (Indirect Gain) and Solar Spaces (Isolated Gain)

There are two other major passive solar heating strategies, Indirect Gain and Isolated Gain. The most common Indirect Gain method is the Trombe Wall, and the most common Isolated Gain method is the solar space.

Trombe walls involve a thick wall painted a dark colour. An inch or so in front of it is glass. Sunlight enters through the glass and is absorbed as heat by the wall. The glass helps prevent heat loss, and wall slowly releases the heat into the rest of the house. Again, a Trombe wall is placed on the south side of the house.

A solar space is basically a glassed-in space on the south side of the house. They are also sometimes known as solar rooms or solaria. Solar spaces can act as greenhouses, and they are sometimes referred to as greenhouses. However, they are not the same as greenhouses designed to grow plants.

The glass is vertical, and there usually isn’t glass overhead. This is so that the glass can be shaded in the summer to avoid overheating. It also means the plants that grow there have less light than they would in a true greenhouse, although more than they would in your house. Since they are attached to the house, you may not want to grow large numbers of plants in it if you’re allergic to mildew. However, if you’ve always wanted a greenhouse,why not use it to grow plants?

These three types of passive solar heating are the most commonly used. While the systems describes here are simple and this overview is simple, there’s a lot more to passive solar design when you really start looking deeply into the subject.

Sources:

Arizona Solar Center

US department of energy: energy efficiency and renewable energy. Passive solar home design.

People turn to solar power for several different reasons:

• High energy prices
• Climate change
• Fossil fuel depletion
• Solar energy costs are coming down

When these factors are taken into account, it’s no wonder that people are going solar. Here are some more data on each:

High Energy Prices

While we’ve been hearing most about high oil prices over the past few years, electricity prices have also been going up in many places. When combined with the price of solar photovoltaics coming down, solar looks a lot more practical than it used to. The recession may have lowered energy prices temporarily, but how long will that last? The volatility in energy prices also makes solar power attractive because you don’t get left vulnerable to energy price spikes when you produce more electricity than you use.

Climate Change

Operating a residential solar power system does not produce CO2. While some CO2 is produced during the making of solar panels and other elements of the system, there are vastly lower emissions than from the production of electricity from oil, gas, or most especially coal. Thus, every solar photovoltaic array very slightly reduces the likelihood of catastrophic climate change.

Fossil Fuel Depletion

The easiest, cheapest oil gets used first. Most oilfields and wells being brought into use now produce oil that is difficult to access or process in some way. This tends to keep oil prices high. It looks increasingly likely that we have hit Peak Oil, which means diminishing supplies of oil in the future no matter how much oil exploration and development we do.

While most electricity does not come from oil, prices for all forms of energy are linked and are likely to become increasingly so as more electric vehicles are made, and even more so if Coal-to-Liquids technology is used on any large scale. In the US, coal is the largest source of electricity. If Coal-to-Liquids plants are built to compensate for Peak Oil, this would increase the price of coal, and therefore that of electricity.

Coal supplies are not endless and it looks increasingly likely that there may be less recoverable coal than commonly thought. This is likely to raise electricity prices in the future. In such an environment renewable energy sources, including solar, look better and better.

Residential Solar Energy is Becoming More Affordable

The current recession has resulted in people buying less. During the high oil prices, producers of solar panels and other components vastly increased capacity. When the recession hit, they found themselves with excess solar photovoltaic systems, components, and raw materials. Prices dropped.

The USA is about to start giving larger rebates for solar which will help increase affordability for a very large, affluent market. This is likely to increase demand for solar energy, which might prevent lowering of prices in the short term, but will likely reduce them in the long term by increasing the capacity of industry. China has also started manufacturing solar panels, which is likely to reduce solar panel price due to economies of scale and cheaper labor in that country.

In California there is at least one company that offers leases of solar photovoltaic systems with guaranteed electricity prices lower than that of some utilities in that area. This increases affordability of solar by eliminating the high start-up costs of home solar systems which act as the largest barrier to going solar for many people.

More Information:

Fossil Fuel Depletion, Peak Oil and Energy Prices:

The Oil Drum

Richard Heinberg’s Museletter

Heinberg, R. 2009 Blackout: coal, climate and the last energy crisis. New Society Publishers.

Trends in Renewables and Renewable Energy News:

Renewable Energy World

There are a lot of jobs in Green Energy that are not the ones we immediately think of. In addition to the people climbing on the roof installing solar panels, there are salespeople, administrators, managers, clerks, lab technicians, engineers, scientists, communications personnel, and entrepreneurs, among many others.

The requirements for these jobs are usually the same as for their equivalents in other industries, with the addition of interest in and enthusiasm for green energy. Experience in the green energy industry is a plus but is often not required, partly because the green energy industry is growing rapidly and there often aren’t enough trained and experienced people available.

There are diplomas and degrees available in green energy, green buildings and other related fields. Many are certificates or diplomas rather than full degrees. These programs are often relatively new, and as the green energy industry matures it is likely that more people working in the industry will have some sort of certification specifically in green energy.

Green Energy Job Sites:

Green energy jobs online

Alternative Energy.com

This job requires tolerance of heights, strength to lift heavy objects
and knowledge of how to install electrical objects safely.

The pay is usually about 15 to 23 dollars an hour. The whole solar sector is a high growth sector of the economy, and job prospects are bright. A high school education is usually expected, along with some construction experience and an apprenticeship or trade school education. However, the exact things employers look for vary somewhat. I culled the list below from actual job ads:

Things employers look for when hiring solar installers are:

• Ability to lift heavy objects (approx. 30-50lbs)
• Ability to work in a variety of positions
• Ability to work in hot sun and awkward spaces
• Not afraid of Heights
• Ability to interact with clients
• Attention to detail
• Ability to keep records and understand documentation
• Driver’s license and clean driver’s record
• Construction-related experience

Knowledge of Computer Software, OSHA safety regulations, and ability to understand blueprints is also often required.

Sources:

SolarInstallerjobs.com

A Day (or Three) in the Life of a Solar Installer

Places Hiring Solar Installers:

Standard Solar

SolarCity

Rec Solar

Batteries are an important component of off-grid and many grid-tied residential solar power systems. They are used to store excess electricity produced by the photovoltaic panels for times when they are producing less electricity than needed, such as at night. Batteries are used in both off-grid applications and in grid-tied battery-backed systems. Batteries for off-grid are usually sized to last through normal use on three cloudy days.

The batteries in grid-tied residential solar power systems are used for backup when the grid goes out. There are usually fewer batteries in these banks because they are only used for backup rather than being used every single night.

The three main types of solar batteries are all lead-acid batteries. However, they are very different from the batteries used in a car because they are deep cycle batteries. This means that they can be drained much more deeply of their charge than shallow cycle batteries such as those used in cars. Car batteries will not stand up to the strain that a residential solar power system will place on them.

Batteries Suitable for Residential Solar Power Systems

Flooded Lead-Acid Solar Batteries

Flooded lead-acid batteries are the cheapest type of lead-acid batteries commonly used to store solar power. They also have the longest life, but require regular maintenance. Distilled water must be added as necessary to replace that lost during charging, and because they are not sealed they must be kept clean and there is a danger of spillage.

Absorbed Glass Matt Sealed Lead-Acid Solar Batteries

These are sealed, and therefore do not require regular maintenance as flooded lead-acid batteries do. They are a newer invention and so far less widely used than flooded lead-acid.

Gelled Electrolyte Sealed Lead-Acid Solar Batteries

These are freezing resistant and are typically used in unheated spaces. They must be charged slowly in order to avoid decreasing capacity, making them better for grid-tied backup than for off-grid uses.

Sources:

Homepower.com

Solar-Batteries.net

The less power you use, the less expensive the home solar system you will need to power your home.   Increasing energy efficiency is a great way to do this.   Recent appliances are more energy-efficient than older ones but the extent of the energy savings varies greatly between different types of appliances.  The two most energy-intensive appliances in most homes are refrigerators and dryers.

Why You Need an Energy Efficient Refrigerator

Refrigerators use a lot of energy.  New refrigerators use a lot less energy than older refrigerators.  There is also a great difference in energy use between different refrigerators.  The standard advice is to buy a new energy efficient refrigerator if your current fridge is more than 10 years old, as the energy savings will pay for the the new refrigerator.

New Energy Star refrigerators use 50% less electricity than the average ten year old refrigerator.   If you live in BC, BC Hydro runs a fridge buy-back program in an effort to reduce electricity use. EnergyStar is a program that certifies energy efficient appliances.   If you live in BC Canada, BC hydro has rebates for buying EnergyStar appliances.   Many other areas probably have similar programs.

Well-maintained appliances are more efficient than poorly maintained ones, as well as doing their jobs better.   If you cannot afford to replace an aging appliance, performing regular maintenance will help minimize its its electricity use.  This will not reduce electricity use to the level of a new appliance, but it will reduce it greatly over a poorly maintained one.

Energy Efficient Dryer or Clothesline?

Dryers use a lot of energy, sometimes as much as the refrigerator despite the fact that they aren’t on all the time. Ideally, one would hang clothes to dry outside, thus using no electricity at all, but in many places this is inconvenient in the winter. Clothes will dry in the cold, but not if it is raining on them.

Drying outside is against bylaws and home owner association regulations in some places. Do be aware that many of these regulations are being challenged and declared illegal, so if you want to dry outside you may be able to do so even if you weren’t a year ago. The movement to make anti-drying regulations illegal is often referred to as the ‘right to dry’ movement, and it is widespread.

Indoor drying racks also work, but do take space while the clothes are drying.  The most inventive indoor drying rack I’ve seen was hung from the ceiling of a kitchen and hauled up and down with a rope and pulley system.  This made extremely efficient use of space and allowed a washer’s worth of clothes to be dried indoors in Britain in the winter.  It worked well enough that the house did not have a dryer.  If you have a small household that does not produce huge amount of laundry this system could well work for you.  It is it is hard to get more electricity efficient than this!

If you do want a dryer, an energy-efficient dryer will save on electricity, although not as much as letting half of each load air-dry.

Energy Efficient Clothes Washers

Front loading washers are more efficient than top loading washers.  If you don’t have large amounts of laundry, a compact washer will save you electricity.  If you do have large amounts of laundry, a full size front loader may be your best bet, as doing one larger wash takes less energy than doing multiple smaller washes.  Some dryers are more efficient than others, so pick an efficient one.

Energy-Efficient Dishwasher or Handwashing?

An energy-efficient dishwasher that is fully loaded uses less hot water than hand washing.  However, this requires that you load it fully.  If you only ever wash small loads at once, hand washing may be more efficient.

There are also energy efficiency improvements to be found with cooking appliances, but they really deserve an article of their own.

There are three main types of solar panel for sale at present: monocrystalline, multicrystalline, and thin film panels. A fourth, sometimes known as vaporware, is sometimes mentioned in the media, but does not yet exist. There is no one best solar panel for every purpose, but each type of solar panel has its own advantages and disadvantages.

Monocrystalline Photovoltaic Panels:

Pros:

• Most efficient, especially in low light conditions
• Less space required for the same amount of power
• More durable than Thin Film

Cons:

• Most expensive per watt
• Production process uses more silicon and more energy
• Rigid

Polycrystalline/Multicrystalline Photovoltaic Panels:

Pros:

• Lower price than Monocrystalline
• Higher efficiency than Thin Film

Cons:

• Higher price per watt than Thin Film
• Rigid
• Lower efficiency than Monocrystalline

Amorphous/Thin Film Photovoltaic Panels:

Pros:

• Cheapest per watt
• Can be made flexible
• Harder to break
• Uses less silicon and less energy during manufacture

Cons:

• Degrades faster
• Lower efficiency
• More space required to produce the same amount of electricity

Vaporware?

This doesn’t actually exist yet, but if it ever does, it will be photovoltaic material that you spray onto a substrate which then becomes a photovoltaic panel.

In Practice:

The type of application has a major impact on which type of solar panel is best for you.  If you want to have solar panels on a backpack where the panels have to be flexible, your only choice is Amorphous/Thin Film panels.  However, if you require the largest possible amount of electricity from the smallest area of solar panel and do not care about it being flexible, then Monocrystalline photovoltaic panels are best.  The choice is up to you.

For More Information:

Northern Arizona wind and sun

Solar Sphere