Renewable Energy Solutions

About Solar Electric Systems

A solar electric system (sometimes known as a solar photovoltaic or solar PV system) captures sunlight using solar cells made from a semiconductor material. The captured sunlight increases the energy of electrons in the semiconductor material, which are released through the photoelectric effect to produce electricity.

Benefits

• Sunlight is an inexhaustible source of renewable energy. Capturing and transforming it into electricity does not produce CO2 or any other greenhouse gas.
• The primary energy source—sunlight—has no cost. Solar electric systems also enjoy generous renewable energy incentives.
• Technological advances, particularly in the development of newer, more efficient, and less expensive semiconductor material, continue to drive down the costs of solar electric systems comparable to other electricity sources.

Design and Installation

Solar electric systems are very flexible—at North Wind, we will work closely with you to design a system that will generate your preferred amount of electricity while also addressing your aesthetic and budget considerations.

Mounting Options

Solar electric systems consist of solar panels that must be mounted in some way to ensure maximum exposure to sunlight. There are three mounting options:

1. Roof-mounted. Roof-mounted solar electric systems consist of solar panels affixed to one or more solar racks, each of which are mounted on a roof. Roof-mounted systems can be deployed on almost any type of roof, which makes them popular for existing homes and buildings.
2. Ground-mounted. Ground-mounted solar electric systems consist of solar panels affixed to one or more solar racks, each of which are mounted on the ground. Ground mounted systems can be placed anywhere, provided they can be conveniently connected to the home, building, or a device that can use the electricity. They can also be combined with tracking systems to track the path of the sun, thereby increasing their productivity.
3. Building-integrated. Building-integrated solar systems are systems that are built right into buildings, e.g., in the roof or walls. The main advantage of this system is that the final roofing or wall material blends into the lines of the building. Building-integrated systems are considerably more expensive, however.

Note that there are a variety of mounting solutions for each of these options. As part of our service, we will help you identify the option that is the most appropriate for your needs and goals.

Grid Connectivity Options

When designing a solar electric system, you have to decide how, if at all, your system will connect to the electricity grid maintained by your utility. There are three grid connectivity options:

1. Grid-tied. Grid-tied solar electric systems generate electricity on their own but are also connected directly to the utility grid. This is a simple, practical configuration because it doesn't require batteries for nighttime power needs; instead, grid-tied systems draw from the grid when sunlight isn't available.
2. Grid-tied with battery backup. Grid-tied solar electric systems with battery backups are similar to grid-tied solar electric systems with one key advantage: during grid power outages, the battery bank provides power to the system, allowing it to continue to function.
3. Off-grid systems. Off-grid systems are not connected to the utility grid. The system stands alone or is combined with a wind turbine or generator to provide electricity to a home or business.

Assessing Your Options

For some sites, North Wind recommends that you conduct a detailed site assessment as a first step in the design and installation of a solar electric system. A site assessment provides information about a site's solar potential, energy efficiency recommendations, ball park system cost, and a guideline for completing the process of designing and installing a system.

Maintenance

Maintenance requirements and costs vary depending on the type of solar electric system. For example, grid-tied non-tracking systems have no moving parts and are virtually maintenance free (except cleaning and possible snow removal). In contrast, systems that include tracking units or batteries require maintenance.

North Wind offers a 10-year warranty on workmanship for all grid-tied systems. This warranty stands beside manufacturer's warranties on parts, which typically include 20-year warranties on solar panels.

We will also service and repair systems installed by other installers as well as provide a battery maintenance service for grid-tied and off-grid systems that use a batter backup.

About Solar Hot Water Systems

A solar hot water system (sometimes known as a solar water heater or solar thermal system) captures energy from sunlight and uses it to heat water for regular use in a home or building. Depending on the design of the system, a solar water system either heats water directly (water is heated by sunlight and then used) or indirectly (a special fluid absorbs the energy from sunlight and transports it to a water tank where it then heats water).

Note: Due to the cold winters experienced in central Wisconsin, indirect solar hot water systems are recommended in most cases.

Benefits

• Sunlight is an inexhaustible source of renewable energy. Capturing and using it to heat water does not produce CO2 or any other greenhouse gas.
• The primary energy source—sunlight—has no cost. Solar hot water systems also enjoy generous renewable energy incentives.
• Solar hot water systems are often cost-effective when properly designed for local climates needs, especially when included in new construction and financed with the rest of the home.

Design and Installation

There are a large number of possible solar hot water system designs, although only a handful are appropriate for year-round use in Wisconsin. At North Wind, one of our goals is to make sure you understand the options that work in Wisconsin and then choose the one that makes the most sense for you.

Collectors

Collectors are responsible for "collecting" the sunlight and providing heat to a solar hot water system. There are two main types of collectors:

1. Flatplate. Flatplate collectors consist of an absorbing sheet made of and/or glazed with some solar absorbent material. Beneath the sheet are coiled tubes within which the liquid in the system (water for a direct system, some other liquid for an indirect system) is heated. Flatplate collectors are very durable and have a strong historical track record of durability.
2. Evacuated. Evacuated tube collectors consist of a series of glass tubes laying next to each other parallel. Inside each tube is a second tube, known as an absorber tube, within which the liquid in the system is heated. Evacuated tubes can be cost effective and can perform well in cold conditions.

Aesthetics

As any property owner can appreciate, the appearance of a property's exterior is as important as its interior. That is why North Wind encourages anyone considering a solar hot water system for the financial and environmental benefits to also consider its aesthetic qualities.

For example, North Wind offers hot water systems from VELUX, a global leader in skylights and solar technology. These systems are designed to integrate as much as possible with the roof on which they are installed. Yet VELUX systems are still some of the most affordable systems available—offering a unique combination of cost-effectiveness and elegance.

Learn more about what North Wind and VELUX can offer you.

Circulation Systems

The major challenge for a solar hot water system in central Wisconsin is avoiding freezing in the winter. This can be accomplished by choosing a closed-loop circulation system, of which two are recommended:

1. Drainback. A drainback system is a closed-loop, indirect solar hot water system that drains liquid from the collector when the pump is turned off (i.e., when the tank is hot and no more heat is needed). This helps prevent freezing in the winter as well as overheating in the summer.
2. Pressurized systems. A pressurized system is a closed-loop, indirect solar hot water system that uses a water/anti-freeze mix as the heating fluid. This offers excellent protection from the winter cold. Also, because it is pressurized, it can use a small pump, one that can even be powered by a small solar electric system.

Assessing Your Options

One of the advantages of a solar hot water system is that there is almost always a system that makes sense for your needs and goals. The disadvantage is that, with so many options and configurations available, it isn't immediately obvious which is the best system for you.

That is why for some sites, North Wind recommends that you conduct a detailed site assessment as a first step in the design and installation of a solar hot water system. A site assessment provides information about your hot water needs, the type of configuration that will be most cost-effective, a ball park system cost, and a guideline for completing the process of designing and installing a system.

About Wind Electric Systems

A small wind electric system harnesses the energy present in the wind to generate electricity. It does this by using the movement of air to rotate the blades of a wind turbine. The rotating blades spin a shaft that is (typically) connected to an alternator where the mechanical energy is turned into electrical energy.

Benefits

• Wind is an inexhaustible source of renewable energy. Capturing and transforming it into electricity does not produce CO2 or any other greenhouse gas.
• The primary energy source—wind—has no cost. Wind electric systems also enjoy generous renewable energy incentives.
• Technological advances have made wind electric systems comparable in cost to other electricity sources.

Design and Installation

When designing a wind electric system, the wind turbine needs to be high enough above the ground to be exposed to an uninterrupted flow of air. In Wisconsin, tall towers of around 100-140 ft. are crucial to achieve good performance.

Other than this requirement, you have significant flexibility when designing a wind electric system to meet your needs. This is particularly true if you select North Wind as your service provider—because we do not maintain an exclusive relationship with a particular turbine manufacturer, you are always able to select the most appropriate equipment for your system.

Turbines

Wind turbines come in many sizes; a careful examination of your electrical load, available wind resources, production goals, and budget is needed to determine which one is right for you.

North Wind can perform a site assessment to help you analyze your options. We can also work with you to select the most appropriate turbines from among a variety of leading manufacturers, including, but not limited to: Proven, Bergey, Abundant Renewable Energy (ARE), and Endurance.

Tower Types

Wind turbines are mounted on towers to ensure maximum exposure to available wind. There are three types of towers commonly used for wind systems:

1. Freestanding tower. A freestanding tower has the smallest footprint of all three options, which means you may install it in tighter spaces. It is the most expensive tower type of the three and must be climbed in order to service or maintenance the turbine.
2. Guyed tower. A guyed tower, which uses three sets of guy wires to provide stability, is typically the least expensive type of tower. It must be climbed to service or maintenance the turbine.
3. Tilt-up tower (TUT). A TUT, which uses four sets of guy wires to provide stability, can be lowered to the ground for required servicing. This makes it convenient for more serious maintenance on turbines, but can take much longer when simply servicing the turbine.

Assessing Your Options

North Wind strongly recommends that you conduct a detailed site assessment as a first step in the design and installation of a wind electric system. A site assessment will evaluate your electrical load, the wind resource for the site, the tower siting options, the appropriate towers and turbines for the application, and rough cost and incentive estimates.

A professional site assessment is also required to qualify for renewable energy incentives Focus on Energy.

Maintenance

Wind turbines are located in harsh environments high above the ground. As a result, regular maintenance is required to ensure maximum uptime over the 20 plus years of expected operation.

Estimating maintenance costs is also an important consideration when considering the true lifetime costs, particularly when deciding between a wind electric or solar electric system.

The purpose of a site assessment is to help you determine whether a particular renewable energy solution makes sense for your goals and needs.

A site assessment is not a sales call. Instead, it is a beneficial, and sometimes necessary, due diligence step that helps ensure that your investment in a renewable energy solution will be a good one.

A site assessment generates a wealth of valuable information that can be used to analyze your needs and prospective solutions. Specific information includes:

• An analysis of your energy needs based on historical records and a professional analysis of the site
• Recommendations on ways to improve energy efficiency (this is one of the easiest ways to improve the cost-effectiveness of a renewable energy solution)
• An evaluation of the strength and/or availability of the renewable energy resource at the site
• Recommendations for the size and type of a cost-effective renewable energy solution, given the analysis of your energy needs and efficiency level (current and potential)
• Details about the recommended renewable energy solution, given the resource availability estimate, including system location, design and estimated installation cost range, and available incentives

Benefits

• A site assessment is not a bid or sales call; it is an independent analysis of your specific needs. In this way, it is similar to a pre-sale home inspection.
• A site assessment is a great way to compare the viability of different renewable energy solutions (e.g., solar electric vs. wind electric). Often we can help you determine relative viability during an initial phone call, but if not, a site assessment certainly can.
• You can use your site assessment to generate cost estimates from any service provider. (Complex or custom renewable energy solutions may require or benefit from an additional site assessment by the service provider you ultimately choose to work with.)
• Many homeowners and businesses in Wisconsin qualify for a subsidy equivalent to 50 percent off the cost of a site assessment from Focus on Energy or their electric utility.
• Most incentives for wind electric systems require a site assessment from a certified site assessor. (Solar electric and solar hot water systems are exempt from this requirement.)