• Zefr™

JLM Wind Energy Zefr™

Urban Arrayed Wind Turbines

Zefr is a Wind Array Turbine System. (WATS) technology consists of several, diverse, yet inter-related pieces of technology combining the fields of aerodynamics, power electronics and digital control into a seamless range of products.

Technology

Revolutionary Wind Technology

The Wind Array Turbine System (WATS) technology consists of several, diverse, yet inter-related pieces of technology combining the fields of aerodynamics, power electronics and digital control into a seamless range of products.

Air Blades

Air Blades were designed using analytical, computational fluid dynamics and empirical techniques. The blades were tested at various wind speeds to provide optimal cut-in speeds without compromising the power output at higher wind speeds. Air Blades are manufactured using high-tech composite materials designed to provide stiffness at a small weight.

The Air Blades are assembled in a hub/seat assembly that allows field configurability of three, five or seven blades enabling the installer to optimize your turbine for the wind regime present at the installation site.

BreezeBox

This innovative electronic module is the unique enabler in taking highly variable power from an array of wind turbines and converting it to a uniform source of energy useable by most off-the-shelf grid-tie inverters.

AutoFurlz

As the turbine experiences higher than 35 MPH winds, AutoFurlz enables the system to reduce the energy incident on the turbine
As the turbine experiences higher than 35 MPH winds, AutoFurlz enables the system to reduce the energy incident on the turbine and hence provide inherent control and safety without taking away the ability of the turbine to continue to generate valuable electrical energy.

Smart GearBox

JLM has implemented a unique gearing mechanism developed specifically for using an array of wind turbines. The SmartGearbox implements an entire gearing mechanism using smart micro-controller technology.

BrakeBox

This unique module is an integrated electromagnetic braking system designed to slow down the turbine at high winds. However, unlike our competitor’s systems, it does not reduce the output of the turbine to zero or bring the turbine to a complete stop.

Turbines

Our turbine module houses all of the components to combine multiple units and to then deploy in any configuration. This module is designed for low wind regimes present in most urban and suburban environments. Depending on the annual average wind speed, it could be configured as a three, five or seven-blade module.

3 Blade

5 Blade

7 Blade

Turbine Nacelle

The Nacelle contains all the necessary hardware and software to convert the wind’s energy to electrical power with the output voltage holding steady at 30V and a current ranging from 0 to 10A. In addition, the Nacelle houses the BreezeBox and BrakeBox modules.

The metal housing is zinc plated, epoxy dipped and powder-coated. This provides a NEMA-4 (IP65) type housing that is guaranteed for 15 years.

The AutoFurlz function is designed to be activated at 35 MPH for the seven-blade rotor and is in integrated into the nacelle.

Output

  • Rated Power: 240 Watts at 35 MPH Generator: 3-phase, rated at 500 Watts
  • Output Current Rating: Up to 8 Amps
  • Output Voltage Rating: 30V constant
  • Brake: Electromagnetic

Physical Dimensions

  • Main Nacelle: 4.75″ x 5.125″ x 5.875″
  • Overall Dimensions: 4.75″ x 13.9″ x 5.875″
  • Main Nacelle: 4.75″ x 5.125″ x 5.875″
  • Weight: 15 lbs.

Temperature Test

  • Twenty-four hours at 50 ℃
  • One hour at up to 90 ℃
  • Five-minute intervals of zero to 150 watts at -20 ℃

Power Curve

Annual Energy Output

Turbine Mounts

The Nacelle for the JLM turbine is designed to be mounted using a virtually limitless number of techniques. Flexible installation is at the core of our philosophy for providing attractive turbine arrays.

Here are some of the standard techniques for installing our turbines…

Parapet Mount:

Most commercial buildings are constructed using either the concrete tilt-up technique or CMUs. In both cases the top edge of the wall extends past the roof line of the building. The exposed roof edge is an ideal location for installing the turbines using the parapet mount. Additionally, the Parapet Mount can also be used to install the turbine on the inside edge of the wall to hide the base. The base footing measures 6″x 10″ and the holes are 3.5″x 8″ on-center, respectively.

Tall Parapet Mount:

The tall parapet mount is 3′ taller than the standard parapet mount. It is used to double turbine density along a roof line by being able to add units between turbines using the standard parapet mount.

Wall Mount:

Wind turbine arrays are installed on or behind a wall using our wall-mount turbine stand. Note that the base is adjustable to any angle ± 90 degrees. The base measure 6”x 10” and the holes are 3.5” and 8” on-center, respectively.

Roof Mount:

JLM’s Roof Mount is used in situations where protruding the roofing layers is not acceptable. The base frame measures 8’x8′, it supports two turbine modules and can be anchored down using sand or gravel bags. This mount is often used when installers are optimizing the siting for the turbines.

Installation

When using the parapet mount, our most common of mounts, the turbines can be placed no closer than 4′-6″ from center to center. Our tall parapet mounts enable you to double the density of turbines along a roof-line making each turbine only 2′-3″ from center when alternating between tall and short parapet mounts.

Inverter System

Since the Small Wind Certification Council (SWCC) does not recognize the array configuration, qualifying our wind turbines using a single string inverter would be impossible. On the other hand, our customers are excited to use multiple wind turbines, configured in an array, to produce a substantial amount of energy.

To provide maximum flexibility in configuration and installation of our arrayed wind turbine technology, each Zefr wind turbine interfaces with its own dedicated micro-inverter. The micro-inverter technology, while common in the PV Solar industry, has never been used in wind turbines due to complex technology barriers. JLM’s Zefr is the first wind turbine in the world that has been successfully interfaced with a micro-inverter.

The micro-inverters used by JLM are UL1741 / IEEE1547 certified and are warrantied for 5 years. In addition, they are compatible with 208V, 3-phase or 240V, single phase grid configurations.

Given the widespread use of these micro-inverters in the PV Solar industry, configuring a hybrid system of wind and solar panels has never been easier. The AC-SGB monitoring module is configuring to not only monitor the production of the wind turbines but also keep track of PV Solar production, as well.

Output Data (AC)

  • Maximum output power
  • Nominal output current
  • Nominal voltage/range
  • Extended voltage/range
  • Nominal frequency/range
  • Extended frequency/range
  • Power Factor
  • Maximum units per 20A

@ 208 VAC

  • 215W
  • 1.0A (arms at nominal duration)
  • 208V/183-229V
  • 208V/179-232V
  • 60.0/59.3-60.5 Hz
  • 60.0/59.2-60.6 Hz
  • >0.95
  • 25 (three phase)

@240 VAC

  • @240 VAC
  • 215W
  • 0.9A (arms at nominal duration)
  • 240V/211-264V
  • 240V/206-269V
  • 60.0/59.3-60.5 Hz
  • 60.0/59.2-60.6 Hz
  • >0.95
  • 17 (single phase)

Efficiency

  • CEC weighted efficiency: 96.0%
  • Peak Inverter efficiency: 96.3%
  • Static MPPT efficiency: 99.6%
  • Dynamic MPPT efficiency: 99.3%
  • Night time power consumption: 46mW

Mechanical Data

  • Ambient temperature range: -40°C to +65°C
  • Operating temperature range (internal): -40°C to +85°C
  • Dimensions (WxHxD): 17.3cm x 16.4cm x 2.5cm (6.8″ x 6.45″‘ x 1.0″)*
  • Weight: 1.6kg (3.5 lbs)
  • Cooling: Natural convection – No fans
  • Enclosure environmental rating: Outdoor – NEMA 6

Features

  • Warranty: 5-year limited warranty
  • Compliance: UL1741/IEEE1547, FCC Part 15 Class B CAN/CSA-C22.2 NO. 0-M91, 0.4-04, and 107.1-01

Configuration

Harness More Energy

Using JLM’s WATS technology, multiple turbine modules can be assembled in a plethora of configurations.

s-Turbine
The patented von Karman vortex stabilizer technology provides the opportunity to enhance the efficiency of our turbines by more than 20% using sails. These sails can be used for advertising and signage.

h-Turbine
The sails are often replaced with Solar panels to build a hybrid system of wind and solar renewable energy.

h-Turbine
The sails are often replaced with Solar panels to build a hybrid system of wind and solar renewable energy.Zefr-H-Turbine-Parking-Lot

Process

Interview

The interview can be performed on the phone, in person or electronically. We’d like to conduct a 10-minute interview to understand what you are looking to accomplish.

Preliminary Analysis

Based on the finding from the Interview, we perform a quick analysis to find out if what you are interested in doing is possible with our technology.

Detailed Analysis

We perform an analytical study of your site, location, building geometry, annual energy estimates, etc. and provide you with a detailed report on the possibilities at your site.

Design Phase

We will work with your chosen contractor and structural engineers to complete the installation process.

Detailed Proposal and Permits

We finalize the design proposal and complete a package of documentation necessary for submission to your local building department for permitting.

Installation

Building codes requires that all solar thermal installations be performed by a licensed commercial contractor. The North American Board of Certified Energy Practitioners also offers a nationally recognized solar thermal certification program. For more information, please see www.nclicensing.org.

Calculator

Energy produced and used can be estimated based on demand schedule, amount of storage and the efficiency of the building’s primary water heating system. Energy savings can then be projected using current utility rates and a realistic projected rate of increase in utility prices (called an escalation rate).

Frequently Asked Questions

Click on the question to reveal the answer.

JLM Energy Zefr™

Q. How do I get a permit?

A.  A wind turbine is a structure that requires a building permit. Zoning regulations often limit the height, placement, and other characteristics of ‘appurtenant’ structures, so a conditional (special) use permit or variance may be necessary. It’s usually best to let your neighbors know about your installation. Be prepared to answer questions and clear up common misconceptions with well-documented facts about small wind turbines.

Contact County Planning or Permitting Department to find out what zoning regulations apply to appurtenant, or non-dwelling, structures on your property. Ask if small wind energy systems are specifically addressed by local ordinance, and if so get a copy of the ordinance. You’ll need to know the permitting procedures and find out what documentation is required for your turbine. You may have to submit a structural plan drafted by an engineer, but documents from your turbine manufacturer or dealer may be enough. (A checklist of common permitting issues is available for California residents.)

If zoning rules list small or residential wind turbines as an approved “conditional” or “special” use for your property, you need only comply with the relevant conditions – which usually pertain to minimum lot size, maximum tower height, setbacks, and electrical code compliance. The manufacturer or dealer may be able to help with the documentation.

If small wind turbines are not an allowed use, you may have to apply for a conditional use permit, which could involve public hearings before you local planning board.

Check local land-use codes carefully for special zoning ordinances that authorities may have overlooked.

A turbine owner in California avoided turbine tower height restrictions through a forgotten wind energy zoning ordinance that had been passed decades earlier.

A zoning variance is a project-specific exception from existing zoning regulations. If the zoning code prohibits structures more than 35 feet, tall, for example, a wind turbine will probably need a variance from the rule unless special provisions have already been inserted for wind energy systems. Local county or city planning boards usually have to approve variances.

An application for a variance should cite the specific rule and list reasons why a structure should be excepted. Height restrictions are a common barrier for wind turbine applicants, who often find height limits set at 35 feet because fire trucks could not pump water higher than that when the code was written. These rules are now obsolete, but residents may nevertheless insist on preserving them because they feel taller structures would negatively alter the neighborhood’s appearance. You should be prepared to explain that the impact of your wind turbine will be minimal. Take note of other tall structures neighbors already accept: Water towers, rooftop satellite dishes, cellular communications towers, etc.

BE PREPARED to answer questions about your project, especially if you have to appear at a public hearing seeking a conditional use permit or variance (Conditional or special use permits do not always require hearings, but a variance will.). A hearing may turn out to be a mere formality, but be ready for anything that might come up. Here are some tips:

Seek the support of your neighbors before the hearing.

Compile documented factual information to reassure anyone worried about noise, visual impact, possible affects on wildlife, and property values.

Planning and zoning officials may be unfamiliar with small wind energy systems, so be prepared to explain the basics. It’s helpful to have photographs of similar installations.

Permitting requirements, procedures, and fees vary widely among counties. Fees for building permits, use permits, zoning permits, and “plot plans” can range from $400 to $1,600. There may be other fees for public notification, hearings, and environmental impact studies costing from a few hundred to several thousand dollars.

Q. Do JLM turbines qualify for a tax credt?

A. On February 17, 2009, President Obama signed into law The American Recovery and Reinvestment Act of 2009 (the ‘Act’). The Act removes the small wind cost caps on Investment Tax Credits (ITC) from the previous legislation. Under the Act, taxpayers can now claim a 30% tax credit for the purchase and installation of qualifying small wind electric systems with rated capacities of 100 kilowatts or less. This credit is available from February 17, 2009 through December 31, 2016.

For non-residential customers the Act allows entities eligible consumers to receive a financial grant from the treasury department in lieu of the tax credit. The system must be placed in service in 2009 or 2010 or placed in service before the credit termination date of January 1, 2013 (provided the construction began in 2009 or 2010). (Source: American Wind Energy Association: Summary of Final Provisions in H.R. 1, the American Recovery and Reinvestment Act (ARRA) of 2009, of Interest to Small Wind Turbine Producers and Consumers).

Q. How does Net Metering work?

A. ‘Net-metering’ is a simplified method of metering the energy consumed and produced at a home or business that has its own renewable energy generator, such as a small wind turbine. Under net metering excess electricity produced by the wind turbine will spin the existing home or business electricity meter backwards, effectively banking the electricity until it is needed by the customer. This provides the customer with full retail value for all the electricity produced. Without net metering the excess production is sold to the utility at a much lower price. Under existing federal law (PURPA, Section 210) utility customers can use the electricity they generate with a wind turbine to supply their own lights and appliances, offsetting electricity they would otherwise have to purchase from the utility at the retail price. But if the customer produces any excess electricity (beyond what is needed to meet the customer’s own needs), the utility purchases that excess electricity at the wholesale or ‘avoided cost’ price, which is much lower than the retail price. The excess energy is metered using an additional meter that must be installed at the customer’s expense. Net metering simplifies this arrangement by allowing the customer to use any excess electricity to offset electricity used at other times during the billing period. In other words, the customer is billed only for the net energy consumed during the billing period.

There are three reasons net metering is important. First, because wind energy is an intermittent resource, customers may not be using power as it is being generated, and net metering allows them to receive full value for the electricity they produce without installing expensive battery storage systems. This is important because it directly affects the economics and pay-back period for the investment. Second, net-metering reduces the installation costs for the customer by eliminating the need for a second energy meter. Third, net metering provides a simple, inexpensive, and easily-administered mechanism for encouraging the use of small-scale wind energy systems, which provide important local, national, and global benefits to the environment and the economy.

Net metering provides a variety of benefits for both utilities and consumers. Utilities benefit by avoiding the administrative and accounting costs of metering and purchasing the small amounts of excess electricity produced by small-scale wind energy facilities. Consumers benefit by getting greater value for some of the electricity they generate and by being able to interconnect with the utility using their existing meter. The only cost associated with net metering is indirect: the customer is buying less electricity from the utility, which means the utility is collecting less revenue from the customer. That’s because any excess electricity that would have been sold to the utility at the wholesale or ‘avoided cost’ price is instead being used to offset electricity the customer would have purchased at the retail price. In most cases, the revenue loss is comparable to having the customer reducing electricity use by investing in energy efficiency measures, such as compact fluorescent lighting, efficient heating and cooling equipment, or other highly-efficient appliances.

The bill savings for the customer (and corresponding revenue loss to the utility) will depend on a variety of factors, particularly the difference between the ‘avoided cost’ and retail prices and the amount of excess electricity produced. In general, however, the difference will be between $10-40 a month for a 10 kilowatt residential wind energy system. Moreover, any utility revenue losses associated with net metering are at least partially offset by administrative and accounting savings, which are not included in the above figures. These savings can exceed $25 a month because, absent net metering, utilities have to separately process the accounts of customers with wind turbines and issue the monthly checks. In practice, these checks can be for as little as 5 cents.

The standard kilowatt-hour meter used for most residential and small commercial customers accurately registers the flow of electricity in either direction. This means the ‘netting’ process associated with net metering happens automatically – the meter spins forward (in the normal direction) when the customer needs more electricity than is being produced, and spins backward when the customer is producing more electricity than is needed in the home or building. The meter registers the net amount of energy produced or consumed during the billing period.

Currently, 28 states require at least some utilities to offer net metering for small wind systems, althoughthe requirements vary from state to state. Most state net metering rules were enacted by state utility regulators, and these rules apply only to utilities whose rates and services are regulated at the state level. In recent years many states have enacted net metering laws legislatively, including California, Connecticut, Massachusetts, Montana, Nevada, New Hampshire, New Jersey, Oregon, Vermont, Virginia, and Washington.

In most of the states with net metering statutes, all utilities are required to offer net metering for small wind systems. To find out whether net metering is available in your location, contact the American Wind Energy Association at the address below, or go to the policy area of the AWEA web site, and follow the links regarding net metering.

Source: Kathy Belyeu, American Wind Energy Association

Q. How much does electricity cost?

A. The cost of electricity depends on where you live, how much you use, and possibly when you use it. There are also fixed charges that you pay every month no matter how much electricity you use. For example, I pay $6/mo. for the privilege of being a customer of the electric company, no matter how much energy I use.

Check your utility bill for the rates in your area. If it’s not on your bill then look it up on the utility’s website.

The electric company measures how much electricity you use in kilowatt-hours, abbreviated kWh. Your bill might have multiple charges per kWh (e.g., one for the ‘base rate’, another for ‘fuel’) and you have to add them all up to get the total cost per kWh.

Most utility companies charge a higher rate when you use more than a certain amount of energy, and they also charge more during summer months when electric use is higher. As an example, here are the residential electric rates for Austin, Texas (as of 11-03):

These figures include a fuel charge of 2.265¢ per kWh.

Q. What is a kilowatt hour?

A.  A 100-watt light bulb uses 100 watts.

A typical desktop computer uses 65 watts.

A central air conditioner uses about 3500 watts.

If your device lists amps instead of watts, then just multiply the amps times the voltage to get the watts. For example: 2.5 amps x 120 volts = 300 watts

Watt-hours

To know how much energy you’re using you have to consider how long you run your appliances. When you run a 1-watt appliance for an hour, that’s a watt-hour. It’s abbreviated Wh. For example:

One 100-watt light bulb on for an hour is 100 watt-hours (100 Wh)

One 100-watt light bulb on for five hours is 500 Wh

Five 100-watt light bulbs on for an hour is 500 Wh

Kilowatt-hours

1,000 watt-hours is a kilowatt-hour (kWh). For example:

One 100-watt light bulb on for an hour, is 0.1 kWh (100/1000)

One 100-watt light bulb on for ten hours is 1 kWh (1 bulbs x 100W x 10h= 1000Wh = 1 kWh)

Ten 100-watt light bulbs on for an hour, is 1 kWh (10 bulbs x 100W x 1h= 1000Wh = 1 kWh)

Ten 50-watt light bulbs on for an hour, is 0.5 kWh

Ten 100-watt light bulbs on for 1/2 an hour, is 0.5 kWh

Running a 3500-watt air conditioner for an hour is 3.5 kWh.

Take a moment to understand the difference between kilowatts and kilowatt-hours. The former is the rate of power at any instant. The latter is the amount of energy used A light bulb doesn’t use 60 watts in an hour, it uses 60 watt-hours in an hour.

The “-hours” part is important. Without it we’d have no idea what period of time we were talking about. If you ever see a reference without the amount of time specified, it’s almost certainly per hour.

Source: http://michaelbluejay.com/electricity/cost.html

Q. What are the dimensions?

A. JLM wind turbine rotors are all 36 in diameter. The nacelle is 4.75 tall by 5.874 deep

Q. How tall is the mounting pole?

A. The overall height includes the mounting pole and turbine. The poles come in 5 foot increments.

Q. What are the startup / shutdown speeds?

A. The low speed JLM Wind turbine will start generating power at a little over 3.5 m/s (8 mph). It is self-starting and requires no power or input to spin up. It does not need over speed control because of its design and will continue to output power as wind increases up to 35 mph. The unit will continue to spin with no damage to the system in winds as high as 80 mph (this is a sustained speed, it can withstand gusts up to 125 mph), however no additional electricity will be generated above maximum output at 35 mph due to restrictions on the inverter.

Q. Is it safe for birds and bats?

A. JLM Wind turbines are completely safe for wildlife because they spin at much lower speeds than horizontal turbines and appear as a solid mass rather than a sharp blurring blade that a bird or bat cannot see or detect.

Q. Does the turbine make noise?

A. The JLM Wind turbines are nearly silent because they operate with tip speeds close to the wind velocity. This dynamic is similar to the wind blowing around any stationary object such as a tree or house. Conventional (horizontal) wind turbines spin at up to 10 times the wind speed which causes the whistling sound that can be heard around them.

Q. What are the mass and loadings?

A. The turbine nacelle weighs approximately 15 lbs not including the mount.

Q. How close can these turbines be mounted to each other?

A. The distance between turbines depends on each individual site. Some locations with strong, consistent prevailing winds can have adjacent turbines 6 feet apart. Other settings might require them to be 30 feet apart to minimize shadowing and a reduction in power output. The optimal layout places consecutive turbines in a line perpendicular to the prevailing wind.

Q. Can I sell electricity to the grid?

A. The laws/regulations vary quite a bit between jurisdictions, and there is a physics component to be careful of. There is a concept called ‘net metering’ where customers connected to the distribution system (as opposed to High Voltage customers) can net off the electricity they produce but not below zero. In other words, customers cannot actually sell surplus to the grid from home generation. The regulations that require electric utilities to buy tend to apply to customers directly connected to the high voltage. Most radial systems (i.e., distribution grids) are not designed to have injections of power at the lowest transformer levels. If the surplus power cannot be taken up by the other homes / businesses connected to the same transformer, then the transformer has to be replaced with a two way one, in order to step up power back to the voltage that runs inter-transformer. So there is a physics reason for this prohibition, not just utility policy.

Q. What safety features are there?

A. JLM turbines are constructed of high strength aluminum and stainless steel for a lifetime of use in extreme environments. The interlocking blade structure provides redundant load paths making a highly damage tolerant unit. The unit has an emergency brake for user initiated shutdown. Under normal expected conditions there is no need to stop the turbine, it will safely operate in 55 mph winds.

Q. Does it have accreditation?

A. The Grid-Tie Inverter has CE marking and is currently undergoing evaluation for UL and cUL listing. The turbine and generator assembly is currently be tested for UL listing. With UL listing the JLM Wind turbines are eligible for rebates under all state Renewable Energy Programs.

Q. What are the economics of small wind?

A. Although small wind systems involve a significant initial investment, they can be competitive with conventional energy sources when you account for a lifetime of reduced or altogether avoided utility costs, especially considering escalating fuel costs.

The cost of buying and installing a small wind energy system typically ranges from about $4,000-7,000 per kilowatt for a grid-connected installation, less than half the cost of a similar solar electric system. The length of the payback period (or, the time it takes to ‘break even’) depends on the system you choose, the wind resource at your site, your power provider’s electricity rates, and financing and incentives available. Small wind owners with strong average wind speeds who can take advantage of rebate programs can usually recoup their investments within fifteen years.

Many states have rebate or tax credit programs in place to encourage small wind and other renewable energy applications. AWEA’s state-by-state pages provide information specific to buying and installing a small wind turbine in each of several U.S. states, including the availability of net metering, local or state incentive programs, and utility incentives.

The cost of a wind system has two components: Initial installation costs and operating expenses. Installation costs include the purchase price of the complete system (including tower, wiring, utility interconnection equipment, power conditioning unit, monitoring system etc.) plus delivery and permitting costs, installation charges, professional fees and taxes.

A 5-kW grid-connected residential-scale system generally costs $20-25,000 to install. The best candidates for these systems are homes and businesses with at least a half acre of property, a Class 3 or better wind resource, and utility bills averaging $150 per month or more. If a net metering arrangement is available from the utility, most of the power generated by a grid-connected system can be valued at the retail rate of electricity, reducing the amount of time it takes for a system to pay for itself.

In California, where net metering and the nation’s highest electric rates are combined with a substantial rebate program and a state tax credit, small wind system owners with strong wind resources can recoup their initial investment in under 5 years, and enjoy essentially free electricity for the remainder of the system’s 30-year useful life. Such a wind energy system can be an excellent, low-risk investment. It can provide a return of up to 15-20%, depending on electric usage and the wind resource.

Smaller systems can offset electricity costs, provide independence they can also can be used to offset electricity costs, or to independently power specific applications such as water pumps or recreational vehicle lights and appliances.

A 2.5 kW turbine, including 20-25 foot tower, utility-tie inverter, utility switch box, hardware and installation components, costs about $15,000 installed. A homeowner can typically save at least 20% off the electric bill with a 2.5 kW turbine, given reasonably strong wind resources.(Savings depend on average annual wind speed, tower height, electrical cost and average electric bill.)

Remote systems may require operating battery storage. Individual batteries cost from $150 to $300 for a heavy-duty, 12 volt, 220 amp-hour, deep-cycle type. Larger capacity batteries, those with higher amp-hour ratings, cost more. A 110-volt, 220 amp-hour battery storage system, which includes a charge controller, costs at least $2,000.

The cost of extending the utility grid to a new home location can be significant, sometimes as high as $20,000-$30,000 for a distance of only one-quarter of a mile. For the same initial investment, a utility-independent renewable energy system can be installed that will meet the electricity needs of an energy-efficient home. Such a system will typically include a combination of a wind turbine, photovoltaics, batteries, an inverter, and a back-up generator. These systems can be cost-effective on a first-cost basis alone, not to mention the avoidance of monthly utility bills for years to come.