What is opportunity charging of a forklift battery?

  • Batteries are charged at rates of 25 A / 100 Ahrs
  • Batteries are charged at every possible opportunity (i.e. breaks, lunch, shift changes)
  • Batteries take an average of 4 – 6 hours daily total to fully recharge the battery
  • Opportunity charging is a good choice for extended shift operations or two-shift operations where battery changing can be eliminated
  • Opportunity charging is good for multi-shift operations and for companies that have space to install strategic charging stations
  • Due to the frequent charging and in order to limit battery gas generation, opportunity chargers are normally set to charge a battery up to 80%-85% SOC throughout the day and back to 100% only once a day (during night hours).

If you have a high energy consumption single shift application or frequently need to run the forklift for more than 1 shift daily or the shift is extended past 8 hours, an opportunity charging system could be a

good fit for you. Opportunity Charging is completed during breaks, between shifts, and any short period of time when the battery is not being used.

Opportunity chargers are programmed to shut off at up to 80%-85% SOC throughout the day the work shifts limiting the cycles used, while controlling the amount of heat generated; and charged back to 100% once a day, usually during the night hours. There are limitations to opportunity changing systems; opportunity charging will not be able meet the demands required in high energy consumption applications or in most 3 shift applications where the trucks are pushed to their limits.

If your operation is conducive to opportunity charging, there are some additional factors to consider:

  • There is an infrastructure cost to locate chargers near break rooms or work areas so it’s convenient for operators to charge at every opportunity.
  • You will have to enforce the discipline to charge during breaks and lunches so the truck can make it through the shifts.
  • You will need to provide nightly down time to restore the battery to 100% SoC between shifts
  • Trucks must be plugged in for a consistent 12 hours to receive an equalization weekly

Even with these factors, opportunity charging could save your company money over the long term by using fewer batteries, eliminating battery change out equipment, and increasing productivity by removing the lost time required for each battery change.

What is fast charging of a forklift battery?

  • Batteries are charged at rates of 40+ A / 100 Ahrs
  • Batteries are charged at every possible opportunity (i.e. breaks, lunch, shift changes)
  • Batteries take an average of 2 -3 hours daily total to fully recharge the battery
  • Batteries are charged to 80%-85% SOC on a daily basis thus eliminating any unnecessary gassing
  • Fast charging is good for three-shift / heavy use operations
  • Fast chargers charge a battery up to 80%-85% SOC throughout the day and back to 100% once a week

If you are running a high production facility where the machines have extreme energy consumption environments or if you are a 24/7 operation a fast charging system may be best for you. Fast charging has a higher charging rate and more frequent charging throughout the day, means that you only require a single battery per truck. The battery can partially charge up during breaks or in-between shifts. This eliminates the need for extra batteries and for battery change-outs between shifts. Operations with limited space will also benefit from fast-charging as you no longer need battery change-out rooms.

Fast charge batteries are designed to minimize temperature rise while maximizing and charge acceptance, meaning they are able accept a higher charge rate while also reducing the operating temperatures of the battery. Fast charge batteries are commonly equipped with dual Intercel connectors, and dual cables with dual connectors for applications requiring charging amps in excess of 300A.

With fast charging, the batteries are only charged to 80%-85% SOC on a daily basis thus eliminating any unnecessary gassing. This eliminates the need for additional batteries and greatly improves truck driver productivity because the time spent changing batteries in two and three shift applications are eliminated. The battery utilization factor jumps to a full 100% (full utilization of the asset) with fast charging.

Battery manufacturers along with PDS also require that all fast charge batteries must be equipped with temperature feedback. Some other accessories should be considered, including a single-point watering system with water level indicator and an optional battery monitor.

No matter the charge rate and system, the lead acid battery will need to perform what is known as an equalization charge once per week. Weekly equalizations to keep batteries healthy balances the specific gravity or acid consistency of the battery and prevents the acid from concentrating at the bottom of the battery, reducing the possibility of battery damage, while also ensuring maximum output efficiency.

The battery decade: How energy storage could revolutionize industries in the next 10 years

The next step: utility-scale storage

The biggest potential market for energy storage is not individual consumers, however, but massive utility companies.

Renewables like wind and solar are providing more and more power for the grid. But until effective energy storage is developed these intermittent sources will continue to rely on fossil fuels.

Put simply, the way the electric grid typically operates at present is that power used is generated just moments before. There’s not a lot of inventory, so supply and demand must be in balance at all times.

But as battery prices fall, more and more utility companies are integrating lithium-ion batteries into their systems. At the moment, they’re primarily used to replace what’s known as peaker plants — plants typically powered by natural gas that are only used at times of peak demand. They’re also beginning to replace diesel generators in places that have continuous power requirements, such as hospitals.

Government incentives and falling solar and wind costs are also accelerating the viability of energy storage.

NextEra Energy is among the country’s largest renewable energy providers, which includes energy storage offerings. In a recent note to clients Credit Suisse called it one of their top investment ideas, based on NextEra’s “heavy exposure to the fast-growing renewables industry” and “world-leading large-scale renewable development business.” Other names offering energy storage include Pennsylvania-based EnerSys, as well as Pinnacle West Capital Corporation, which in February announced plans to add 850 megawatts of battery storage in Arizona over the next 5 years.

Currently, the largest lithium ion battery installation is located in South Australia and powered by Tesla. It has 100 megawatt capacity, which, according to the site, allows it to power 30,000 homes when dispatching at peak output. In November France-based Neoen, which operates the site, announced a 50% expansion, which will raise capacity to 150MW.

Renewable energy equipment makers and operators, as well as chemical and materials companies could also benefit if storage makes wind and solar power more feasible. Osborne noted that new software will be required to help utility companies understand power needs as renewables and electric vehicles draw from the grid.

The next decade

Costs that remain high are among the reasons preventing a surge in lithium-ion battery grid integration. Another factor is that this specific type of battery may not necessarily prove to be the best suited to storing energy for longer periods of time. They’ve also been known to catch fire, and there are issues with some of the required components like cobalt, almost half of which comes from Congo. Recycling and the environmental impact of metals extraction are other issues to watch.

Billions of dollars are being spent to find alternatives. Solid-state batteries — which use sodium, for example, instead of liquid electrolytes — is one possible option, as are flow batteries, which use tanks of electrolytes to store energy. But neither of these are viable options just yet.

While the exact type of battery that will win out is unknown, what’s certain is that batteries will play an even larger role in powering our lives going forward.

“Massive investments in battery manufacturing and steady advances in technology have set in motion a seismic shift in how we will power our lives and organize energy systems as early as 2030,” researchers from Rocky Mountain Institute wrote in Breakthrough Batteries: Powering the Era of Clean Electrification.

Powering Your Cell Towers

Historically, cell tower power was a lot like the electrical grid: essential, reliable, taken for granted, a tad dull.

 

Today, cell tower power is an exciting source of technical and business innovation running at an ever-faster tempo. Global climate change is driving change in renewable green energy (e.g., solar, wind, hydrogen fuel cells), government regulations (e.g., carbon credits), and disaster preparedness (e.g., hardening measurement and control systems before the next massive earthquake or tsunami hits). Further, the Internet of Things can only scale up to the massive scale required if cheap, reliable power is available on demand. To learn more about the future of cell tower power, read this white paper and info graphic. Then reach out to your Westell representative who can introduce you to experts and innovators in this field. 

 

There are many ways to improve efficiency, reliability, and scalability of your power system and earn a great return on your investment. In networks, much like real estate, the key is location, location, location. When planning for new network capacity, whether retrofits, acquisitions, or greenfield builds, location is absolutely essential. For carriers, location is important for coverage. For tower owners, location is important to attract and retain tenants. Once the tower is sited, the next essential step is electrical system design. A well thought-out electrical system design will balance efficiency, reliability, and scalability. When a tower’s power system is running well, carriers and owners are poised to deliver a great experience to end users and a profitable bottom line to their shareholders. 

 

By understanding the basic power system components and how they play together, it is easier to see how engineering and operational tradeoffs are made, how best practices can be implemented, and how return on investment (ROI) can be calculated. Most cell tower electrical systems face similar challenges.

Learn about the differences in nickel-cadmium and nickel-metal-hydride

For 50 years, portable devices relied almost exclusively on nickel-cadmium (NiCd). This generated a large amount of data, but in the 1990s, nickel-metal-hydride (NiMH) took over the reign to solve the toxicity problem of the otherwise robust NiCd. Many of the characteristics of NiCd were transferred to the NiMH camp, offering a quasi-replacement as these two systems are similar. Because of environmental regulations, NiCd is limited to specialty applications today.

Nickel-cadmium (NiCd)

Invented by Waldemar Jungner in 1899, the nickel-cadmium battery offered several advantages over lead acid, then the only other rechargeable battery; however, the materials for NiCd were expensive. Developments were slow, but in 1932, advancements were made to deposit the active materials inside a porous nickel-plated electrode. Further improvements occurred in 1947 by absorbing the gases generated during charge, which led to the modern sealed NiCd battery.

For many years, NiCd was the preferred battery choice for two-way radios, emergency medical equipment, professional video cameras and power tools. In the late 1980s, the ultra-high capacity NiCd rocked the world with capacities that were up to 60 percent higher than the standard NiCd. Packing more active material into the cell achieved this, but the gain was shadowed by higher internal resistance and reduced cycle count.

The standard NiCd remains one of the most rugged and forgiving batteries, and the airline industry stays true to this system, but it needs proper care to attain longevity. NiCd, and in part also NiMH, have memory effect that causes a loss of capacity if not given a periodic full discharge cycle. The battery appears to remember the previous energy delivered and once a routine has been established, it does not want to give more.

Nickel-metal-hydride (NiMH)

Research on nickel-metal-hydride started in 1967; however, instabilities with the metal-hydride led to the development of the nickel-hydrogen (NiH) instead. New hydride alloys discovered in the 1980s eventually improved the stability issues and today NiMH provides 40 percent higher specific energy than the standard NiCd.

 

Nickel-metal-hydride is not without drawbacks. The battery is more delicate and trickier to charge than NiCd. With 20 percent self-discharge in the first 24 hours after charge and 10 percent per month thereafter, NiMH ranks among the highest in the class. Modifying the hydride materials lowers the self-discharge and reduces corrosion of the alloy, but this decreases the specific energy. Batteries for the electric powertrain make use of this modification to achieve the needed robustness and long life span.

 

High self-discharge is of ongoing concern to consumers using rechargeable batteries, and NiMH behaves like a leaky basketball or bicycle tire. A flashlight or portable entertainment device with a NiMH battery gets “flat” when put away for only a few weeks. Having to recharge the device before each use does not sit well with many consumers especially for flashlights that sit on standby for the occasional power-outage; alkaline keeps the charge for 10 years. 

 

The Eneloop NiMH by Panasonic has reduced the self-discharge by a factor of six compared to earlier versions by Sanyo. These improvements were made possible with changes in chemical composition and a modified separator. This means you can store the charged battery six times longer than a regular NiMH before a recharge becomes necessary. The Panasonic NiMH are also said to perform well at cold temperatures. The drawback of the Eneloop to regular NiMH is a slightly lower specific energy.

How does the Lead Acid Battery Work?

nvented by the French physician Gaston Planté in 1859, lead acid was the first rechargeable battery for commercial use. Despite its advanced age, the lead chemistry continues to be in wide use today. There are good reasons for its popularity; lead acid is dependable and inexpensive on a cost-per-watt base. There are few other batteries that deliver bulk power as cheaply as lead acid, and this makes the battery cost-effective for automobiles, golf cars, forklifts, marine and uninterruptible power supplies (UPS).

 

The grid structure of the lead acid battery is made from a lead alloy. Pure lead is too soft and would not support itself, so small quantities of other metals are added to get the mechanical strength and improve electrical properties. The most common additives are antimony, calcium, tin and selenium. These batteries are often known as “lead-antimony” and “lead calcium.”

 

Adding antimony and tin improves deep cycling but this increases water consumption and escalates the need to equalize. Calcium reduces self-discharge, but the positive lead-calcium plate has the side effect of growing due to grid oxidation when being over-charged. Modern lead acid batteries also make use of doping agents such as selenium, cadmium, tin and arsenic to lower the antimony and calcium content.

 

Lead acid is heavy and is less durable than nickel- and lithium-based systems when deep cycled. A full discharge causes strain and each discharge/charge cycle permanently robs the battery of a small amount of capacity. This loss is small while the battery is in good operating condition, but the fading increases once the performance drops to half the nominal capacity. This wear-down characteristic applies to all batteries in various degrees.

 

Depending on the depth of discharge, lead acid for deep-cycle applications provides 200 to 300 discharge/charge cycles. The primary reasons for its relatively short cycle life are grid corrosion on the positive electrode, depletion of the active material and expansion of the positive plates. This aging phenomenon is accelerated at elevated operating temperatures and when drawing high discharge currents.

 

Charging a lead acid battery is simple, but the correct voltage limits must be observed. Choosing a low voltage limit shelters the battery, but this produces poor performance and causes a buildup of sulfation on the negative plate. A high voltage limit improves performance but forms grid corrosion on the positive plate. While sulfation can be reversed if serviced in time, corrosion is permanent.

 

Lead acid does not lend itself to fast charging and with most types, a full charge takes 14–16 hours. The battery must always be stored at full state-of-charge. Low charge causes sulfation, a condition that robs the battery of performance. Adding carbon on the negative electrode reduces this problem but this lowers the specific energy. 

 

Lead acid has a moderate life span, but it is not subject to memory as nickel-based systems are, and the charge retention is best among rechargeable batteries. While NiCd loses approximately 40 percent of their stored energy in three months, lead acid self-discharges the same amount in one year. The lead acid battery works well at cold temperatures and is superior to lithium-ion when operating in subzero conditions. According to RWTH, Aachen, Germany (2018), the cost of the flooded lead acid is about $150 per kWh, one of the lowest in batteries.

How do Battery Chargers Work? Types of Chargers

The most basic charger was the overnight charger, also known as a slow charger. This goes back to the old nickel-cadmium days where a simple charger applied a fixed charge of about 0.1C (one-tenth of the rated capacity) as long as the battery was connected. Slow chargers have no full-charge detection; the charge stays engaged and a full charge of an empty battery takes 14–16 hours. When fully charged, the slow charger keeps NiCd lukewarm to the touch. Because of its reduced ability to absorb over-charge, NiMH should not be charged on a slow charger. Low-cost consumer chargers charging AAA, AA and C cells often deploy this charge method, so do some children’s toys. Remove the batteries when warm.

 

The rapid charger falls between the slow and fast charger and is used in consumer products. The charge time of an empty pack is 3–6 hours. When full, the charger switches to “ready.” Most rapid chargers include temperature sensing to safely charge a faulty battery.

 

The fast charger offers several advantages and the obvious one is shorter charge times. This demands tighter communication between the charger and battery. At a charge rate of 1C, which a fast charger typically uses, an empty NiCd and NiMH charges in a little more than an hour. As the battery approaches full charge, some nickel-based chargers reduce the current to adjust to the lower charge acceptance. The fully charged battery switches the charger to trickle charge, also known as maintenance charge. Most of today’s nickel-based chargers have a reduced trickle charge to also accommodate NiMH.

 

Li-ion has minimal losses during charge and the coulombic efficiency is better than 99 percent. At 1C, the battery charges to 70 percent state-of-charge (SoC) in less than an hour; the extra time is devoted to the saturation charge. Li-ion does not require the saturation charge as lead acid does; in fact it is better not to fully charge Li-ion — the batteries will last longer but the runtime will be a little less. Of all chargers, Li-ion is the simplest. No trickery applies that promises to improve battery performance as is often claimed by makers of chargers for lead- and nickel-based batteries. Only the rudimentary CCCV method works.

 

Lead acid cannot be fast charged and the term “fast-charge” is a misnomer. Most lead acid chargers charge the battery in 14–16 hours; anything slower is a compromise. Lead acid can be charged to 70 percent in about 8 hours; the all-important saturation charge takes up the remaining time. A partial charge is fine provided the lead acid occasionally receives a fully saturated charge to prevent sulfation.

 

The standby current on a charger should be low to save energy. Energy Star assigns five stars to mobile phone chargers and other small chargers drawing 30mW or less on standby. Four stars go to chargers with 30–150mW, three stars to 150–250mW and two stars to 250–350mW. The average consumption is 300mW and these units get one star. Energy Star aims to reduce current consumption of personal chargers that are mostly left plugged in when not in use. There are over one billion such chargers connected to the gird globally at any given time.

How do Battery Chargers Work? Discover which charger is best for your application

A good battery charger provides the base for batteries that are durable and perform well. In a price-sensitive market, chargers often receive low priority and get the “after-thought” status. Battery and charger must go together like a horse and carriage. Prudent planning gives the power source top priority by placing it at the beginning of the project rather than after the hardware is completed, as is a common practice. Engineers are often unaware of the complexity involving the power source, especially when charging under adverse conditions

Chargers are commonly identified by their charging speed. Consumer products come with a low-cost personal charger that performs well when used as directed. The industrial charger is often made by a third party and includes special features, such as charging at adverse temperatures. Although batteries operate below freezing, not all chemistries can be charged when cold and most Li-ions fall into this category. Lead- and nickel-based batteries accept charge when cold but at a lower rate.

 

Lead- and lithium-based chargers operate on constant current constant voltage (CCCV). The charge current is constant and the voltage is capped when it reaches a set limit. Reaching the voltage limit, the battery saturates; the current drops until the battery can no longer accept further charge and the fast charge terminates. Each battery has its own low-current threshold.

Nickel-based batteries charge with constant current and the voltage is allowed to rise freely. This can be compared to lifting a weight with a rubber band where the hand advances higher than the load. Full charge detection occurs when observing a slight voltage drop after a steady rise. To safeguard against anomalies, such as shorted or mismatched cells, the charger should include a plateau timer to assure a safe charge termination if no voltage delta is detected. Temperature sensing should also be added that measures temperature rise over time. Such a method is known as delta temperature over delta time, or dT/dt, and works well with rapid and fast charge.

 

A temperature rise is normal with nickel-based batteries, especially when reaching the 70 percent charge level. A decrease in charge efficiency causes this, and the charge current should be lowered to limit stress. When “ready,” the charger switches to trickle charge and the battery must cool down. If the temperature stays above ambient, then the charger is not performing correctly and the battery should be removed because the trickle charge could be too high.

 

NiCd and NiMH should not be left in the charger unattended for weeks and months. Until required, store the batteries in a cool place and apply a charge before use.

Lithium-based batteries should always stay cool on charge. Discontinue the use of a battery or charger if the temperature rises more than 10ºC (18ºF) above ambient under a normal charge. Li ion cannot absorb over-charge and does not receive trickle charge when full. It is not necessary to remove Li-ion from the charger; however, if not used for a week or more, it is best to place the pack in a cool place and recharge before use.

CELL TOWER BATTERY THEFTS : GLOBAL PROBLEM

n recent years, telecom sites all over the world have been suffering from battery theft.

The Problem

The assumption was that batteries were being stolen for recycling lead contents or for self-use. But it turns out that a large part is smuggled outside the borders and some are even sold in the local black market.

This phenomenon is increasing. Mobile network operators are spending hundreds of thousands of dollars every year on replacing stolen batteries and security.

Cell tower Battery thefts became a global problem!

The theft of the batteries and the damage to telecom sites has the potential to cause a serious impact not only on the industry, but also on the economy, by causing disruptions to the network provisions, while disconnecting many areas from services, including essential services. 

This phenomenon also does not overlook LIB batteries, which are frequently stolen.

Additional Challenges

The 5G era is approaching and brings with it additional challenges:

  • Increase in the number of sites
  • Increase of network energy consumption
  • High electricity costs

This will enhance the phenomenon and its implications!

Mobile network operators are trying to deal with this phenomenon in different ways:

  • Installing security cameras
  • Installing battery safes
  • Increase the amount of security personnel
  • Utilizing heavy, 2V batteries
  • And more…

The Solution

Easily and commonly done by many companies to protect battery cell towers from theft is to use metal frames that form like a tightly enclosed cage so that thieves are hard to take because there are no gaps or if you want to be more modern you can use a tracking device if the battery is successfully carried by a thief then we will find out where the battery is located. It has proven itself worldwide and saved hundreds of thousands of dollars to its customers.

A Solar-Powered Home: Will It Pay Off?

Homeowners who install photovoltaic power systems receive numerous benefits: lower electric bills, lower carbon footprints, and potentially higher home values. But these benefits come with significant installation and maintenance costs, and the magnitude of the gains can vary widely from one house to another. This article will help homeowners make the financial calculations required to determine the viability of solar power in their homes.

Photovoltaic Solar Power

Photovoltaic (PV) solar technology has been around since the 1950s, but, thanks to declining solar module prices, it has only been considered a financially viable technology for widespread use since the turn of the millennium.

Solar panel size is quoted in terms of the theoretical electrical output potential in watts. However, the typical output realized for installed PV systems—known as the “capacity factor”—is between 10% and 20% of the theoretical output. A 3 kilowatt-hour (kWh) household system running at a 15% capacity factor would produce 3kW*15%*24hr/day*365days/year = 3,942 kWh/year, or roughly one-third of the typical electricity consumption of a U.S. household. But this calculation may be misleading because there is little reason to speak of “typical” results; in fact, solar may make sense for one household, but not for the house next door. This discrepancy can be attributed to the financial and practical considerations considered in determining viability.

Costs

Solar power is capital intensive, and the main cost of owning a system comes upfront when buying the equipment. The solar module will almost certainly represent the largest single component of the overall expense. Other equipment necessary for installation includes an inverter (to turn the direct current produced by the panel into the alternating current used by household appliances), metering equipment (if it is necessary to see how much power is produced), and various housing components along with cables and wiring gear. Some homeowners also consider battery storage. Historically, batteries have been prohibitively expensive and unnecessary if the utility pays for excess electricity that is fed into the grid (see below). The installation labor cost must also be factored in.

In addition to installation costs, there are some further costs associated with operating and maintaining a PV solar array. Aside from cleaning the panels regularly, inverters and batteries (if installed) generally need replacement after several years of use.

While the above costs are relatively straightforward—often a solar installation company can quote a price for these for a homeowner—determining subsidies available from the government and/or your local utility can prove more of a challenge. Government incentives change often, but historically, the U.S. government has allowed a tax credit of up to 30% of the system’s cost. More details on incentive programs in the U.S., including programs within each state, can be found on the Database of State Incentives for Renewables & Efficiency (DSIRE) website. In other countries, such information is often available on government or solar advocacy websites. Homeowners should also check with their local utility company to see whether it offers financial incentives for solar installation, and to determine what its policy is for grid interconnection and for selling excess power into the grid.

Benefits

A significant benefit to PV installation is a lower energy bill, but the magnitude of this benefit depends on the amount of solar energy that can be produced given the available conditions and the way in which utilities charge for electricity.

The first consideration is the solar irradiation levels available in the home’s geographical location. When it comes to using solar panels, being closer to the equator is generally better, but other factors must be considered. The National Renewable Energy Laboratory (NREL) produces maps for the U.S. showing solar irradiation levels; the tools on its website provide detailed solar information for specific locations within the U.S. Similar maps and data are available in other countries as well, often from government environmental agencies or renewable energy organizations. Equally important is the home’s orientation; for rooftop arrays, a south-facing roof without trees or other objects obstructing sunlight maximizes the available solar energy. If this is not available, panels can be mounted on external supports and installed away from the house, incurring additional costs for the extra hardware and cables.

The second consideration is the timing of solar power production, and how utilities charge for electricity. Solar power generation occurs primarily during the afternoon and is higher during summer, thus corresponding relatively well to overall electricity demand in warm climates because it is at these times that air conditioners consume the most energy. Consequently, solar power is valuable because the alternative methods of energy production (often natural gas power plants) used to meet peak energy demand tend to be expensive. But utilities often charge residential consumers a flat rate for electricity, regardless of the time of consumption. This means that instead of offsetting the expensive cost of peak electricity production, homeowners’ solar power systems merely offset the price they are charged for electricity, which is much closer to the average cost of power production.

Calculating the Financial Viability and the “Levelized” Cost of Electricity

Once the above costs and benefits are determined, a solar system can theoretically be evaluated using the discounted cash flow (DCF) method. Outflows at the beginning of the project would consist of installation costs (net of subsidies), and inflows would arrive later in the form of offset electricity costs (both directly and through net metering).

Rather than using DCF, the viability of solar power is usually evaluated by calculating the levelized cost of electricity (LCOE), then comparing it to the cost of electricity charged by the local utility. The LCOE for household solar will typically be calculated as cost/kilowatt-hour ($/kWh or ¢/kWh) – the same format commonly used on electricity bills. To approximate the LCOE, one can use the following equation:

LCOE ($/kWh) = Net Present Value (NPV) of the Lifetime Cost of Ownership ($) / Lifetime Energy Output (kWh)

The Bottom Line

Determining whether to install a PV solar system may seem like a daunting task, but it is important to remember that such a system is a long-term investment. In many locations, solar power is a good choice from a financial perspective. Even if the cost of solar power is found to be marginally more expensive than electricity purchased from a utility, homeowners may wish to install solar power to avoid future potential fluctuations in energy costs, or may simply wish to look beyond their personal financial motivations and use solar for “green” living.