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Frequently Asked Questions


Find quick answers to the most common questions below. Select a category to browse by topic.

  • General FAQ
    Do you offer free estimates? Yes. We even publish a price sheet on our website. Get a custom recommendation by submitting a project form. Visit our Get Started page for a list of resources. Where are you located? We are in Rapid City, SD. Please see our contact page for details. What is your service area? We serve the Black Hills area within 100 miles of Rapid City, South Dakota. Are you a contractor or retailer? We are electrical contractors providing complete system design, sales, and service. We are not a retailer. What types of systems do you offer? We install residential and commercial solar power and energy storage systems for buildings, including electric vehicle connectors, power distribution panels, and related electrical services. Please note: We do not sell or service systems for recreational vehicles, mobile applications, hot water/air collectors, wind power systems, off-the-shelf/retail products. Do you support DIY or 3rd-party installations? We only offer complete design/installation services at this time. We do not support DIY or 3rd party system design or installation and do not install systems or components sold by others. If another party designed or installed a system you already own, please contact them as they are more familiar with it and are responsible for permits, customer support, and warranty-related issues. How long does it take to get solar installed? Depending on the complexity, projects usually take two to five days to system design, estimate/quote, and prepare permitting and interconnection paperwork. On-site installation time varies from two to four days in most cases. What is your project lead time? Lead times vary seasonally. On average, we have a one-month lead time. Get started planning your project with is in the first or second quarter to get scheduled in the same year. By late summer we may be fully-booked for the year. Installations are weather-dependent, so projects quoted in the winter may be scheduled for springtime. Are there tax credits or incentives? Yes. A federal tax credit allows you to claim a 30% tax credit on solar power and energy storage system installations. See IRS form 5695. Learn more here: What is your certification/experience? Our team includes PV Installation Professional certification by the North American Board of Certified Energy Practitioners including Master and Journeyman electricians. Are you licensed? Yes, we hold building (Rapid City: AEC2369) and electrical contractor licenses (SD: EC-3543, Rapid City: AEC3533, Wyoming: M-52663). Are you insured? Yes, we are commercially insured by Acuity.
  • Purchasing
    How do I make a purchase? Following an initial estimate, we will provide a formal quote for your acceptance, followed by a purchase agreement (contract) for your signature. What are your payment options? We accept payment by check. Most projects require a 50% down payment and the balance due at completion. We accept credit cards only for transactions under $1,000. Do you lease or finance? We do not lease or finance directly. To learn about third-party financing options click here.
  • Solar Power
    How much solar power do I need? For most homes, a solar panel system between 3 to 6 kW is effective for reducing energy bills and meeting energy needs for most of the year. Larger systems, up to 10 kW, are suitable for bigger homes and achieving net-zero energy goals. Some larger homes or those with higher-than-average energy requirements may need up to 20 kW for greater energy independence. The recommended system size depends on available roof space, monthly electricity usage, and your specific needs. You can also start with a smaller system and expand it later. Will solar power run my air conditioning? Yes, solar power is well-suited for air conditioning since A/C units are used most during sunny periods. In many cases, solar power can significantly reduce or eliminate the cost of air conditioning. Will solar power run my electric heat? Partially. Solar power will contribute to electric heating during the day, but most heating is needed at night. If using a battery to power heaters at night, the battery must be large to avoid quick depletion, as electric heaters consume a lot of power continuously. Heat pumps are an efficient alternative to resistive heaters (e.g., cove or baseboard), but generally speaking, solar power alone isn't a sufficiently reliable power source for heating in most circumstances. Can I charge my electric vehicle with solar? Yes. Charging your vehicle during the daytime is most efficient. The required solar power capacity to eliminate EV charging costs depends on the number of miles driven daily. For more details, refer to the EV section of this FAQ. Will solar reduce my power bill and pay for itself? Yes. Solar power reduces the amount of electricity you draw from the grid, thereby lowering your utility bills. The payback period for your investment depends on various factors, including utility rates. Solar systems have a lifespan of over 20 years, ensuring they can provide a reliable return on investment in most situations. Do batteries improve savings or payback? Battery systems help reduce bills by storing excess solar energy for nighttime use and lowering peak demand charges. While not typically installed solely for ROI, batteries provide essential backup power, protecting refrigeration and other critical appliances during grid outages. Is there a warranty? Yes, all system components include a manufacturer warranty. Major components, including Powerwall and other lithium battery systems, have a minimum of 10 years manufacturer limited warranty. Our tier 1 solar panels come with a 25- to 30-year performance warranty. Black Hills Solar also guarantees quality workmanship and handles warranty processing, repairs, and replacements. Is it better to install solar panels on the roof or on the ground? Both roof and ground mounts have their benefits. For more details on this topic, refer to the Knowledge Base section of our website. Roof Mounts: Pros: Cost-effective Quick installation Does not use up land space Cons: Limited by roof orientation and pitch Panels need to be removed for re-roofing May be difficult to access for snow removal Ground Mounts: Pros: Optimizable orientation and tilt for best performance Easier snow removal Higher efficiency due to better air circulation and cooling Cons: Higher cost due to construction and site work Requires a 24" deep trench for the solar power line May need fencing for protection
  • Battery Systems
    Do I need a battery with solar? Not necessarily, but batteries are highly recommended. They provide backup power and store excess solar energy for use at night. Batteries can also help reduce power bills when time-based rates apply. Without a battery, a basic grid-tied solar power system is an option, but much of the generated energy may go to the grid instead of powering your home. Can I add a battery later? Yes. You can add a battery system to your solar power setup at a later date. While some people choose to install the solar power system first and add a battery later, installing both together can reduce overall installation costs. What can I backup? In most cases, the battery system can back up the entire property, provided the battery can handle the largest appliance or load. Sometimes, large appliances or electric heaters may be excluded from backup, leaving only essential items powered when off-grid. How much backup time can I expect? Backup time depends on energy usage, available solar power, and battery capacity. At a minimum, a battery will power essentials for about a day. In many cases, one battery can power essentials like lighting and refrigeration for a week or longer on a single charge. With proper load management and adequate solar power for recharging, backup power can be continuous. Can I go off-grid? A special feature of the Tesla Powerwall system is the ability to select to "Go Off-Grid" using the Tesla App. Going off-grid this way simulates a grid power outage by automatically disconnecting from the grid. This feature allows the homeowner to practice load management and improve self-sufficiency. If the battery runs low, the system will automatically connect back to the grid to avoid a power outage. Note: truly off-grid homes are permanently disconnect from the grid. What is the battery lifespan? Many household lithium-type batteries come with a 10-year warranty, guaranteeing at least 70% of the original capacity by the end of the warranty period.
  • EV Charging
    An average electric vehicle (EV) uses about 30 kWh per 100 miles, or roughly 0.3 kWh per mile. The most efficient EVs currently use around 0.25 kWh per mile, while some larger EV vehicles require more energy per mile than average. How many solar panels are needed for car charging? On average, one solar panel generates 1 to 2 kWh per day, depending on location and time of the year. For example, a 6 kW solar PV system can generate approximately 18 to 24 kWh per day (assuming 3 to 4 kWh per kW per day) in optimal conditions. This would be enough to charge an EV for about 60 to 80 miles, considering 0.3 kWh per mile. During winter, the output may drop to 9 to 12 kWh per day, providing enough energy for about 30 to 40 miles of driving. How do I calculate the solar capacity needed for my EV? To determine the solar capacity needed to offset your EV's energy use, consider your average daily driving distance. For instance, driving 30 miles per day requires about 9 kWh of energy. A solar PV system with a capacity of 3 to 4 kW can produce 9 to 16 kWh per day in optimal conditions, offsetting this energy use for most of the year. Keep in mind that any excess solar power will be used by your home, so oversizing the system is generally not an issue. Example Calculation: Average daily driving: 30 miles Energy needed: 30 miles * 0.3 kWh/mile = 9 kWh/day Solar PV system needed: To generate 9 kWh/day, a 3 to 4 kW system (producing 9 to 16 kWh/day) would be sufficient, considering typical solar irradiance and system efficiency. What type of solar power system do I need to charge my EV? We recommend using a smart solar EV charger, which can: Direct solar power to the vehicle Reduce or eliminate grid power usage for the vehicle Schedule charging times If your EV charger is not integrated into the solar power system, solar power will go to all household loads, potentially increasing grid power usage for vehicle charging. Regardless, solar power will help reduce overall grid power consumption. Can I charge my EV at night? Yes, you can charge your EV at night. During the day, solar power will supply your home, while at night, your vehicle will use grid power. Depending on your utility rates and home energy usage, you might still see a net reduction in your electricity bill. Additionally, home batteries can be used for nighttime vehicle charging, though they need to have sufficient capacity. Will EV charging increase demand charges? EV charging can significantly increase power usage at one time, potentially raising demand charges if your utility bill includes them. To manage these charges, you can use: A smart charger A demand controller A smart breaker panel Home batteries These tools can help minimize peak power usage and associated costs.
  • Installation Requirements
    Does solar work if there is shading? Shading from trees or nearby objects will reduce the performance of solar panels. Ideally, solar panels are installed in areas with minimal shading. Locations with significant shading are not suitable for solar installations, or they may require additional components to mitigate shading losses. Could my roof leak? We guarantee that our solar roof attachments are completely waterproof. We use roof attachments that are both UL-listed and rated for the lifespan of your roof. If your roof is in poor condition or needs repairs, we recommend addressing these issues before installing solar panels. Do I need an electrical upgrade? In most cases, no electrical upgrade is needed. This is especially true with Tesla systems. Most systems only require a single two-pole breaker in the existing breaker panel. However, some systems or specific situations might require moderate to extensive electrical upgrades or additional equipment. What is required by the utility? Your utility provider requires an interconnection application (typically completed by the installer), an interconnection agreement (signed by the property owner), and proof of homeowners insurance. This process is straightforward, and we will assist you with it. Once the installation is complete, your electric utility provider will configure the meter to track energy flowing back to the grid, applying the credit to your bill. Is permitting required? Yes, permits are required. We will obtain all necessary permits, which may include a Rapid City wiring permit, a South Dakota wiring permit, or a Pennington County building permit. How long does an installation take? An average project takes 2 to 4 days on-site, depending on the location, system size, type of system, and necessary electrical work. The total project time, including site evaluation, system design, permitting, scheduling, and installation, can range from 1 to 4 weeks.
  • Technical Specifications
    How much power/energy does a solar panel actually produce? In full sun a solar panel produces 70% to 90% of its rated power on average, depending mostly on the the angle of the sun to the panels but also the temperature of the solar cells. Over the course of an average day, each solar panel will generate 0.5 to 3 kWh of energy, depending on the panel, its orientation, the season and weather conditions. How big are the solar panels? We offer two sizes of solar panels. The residential size is approximately 75x42 inches. The commercial size are up to 90x45 inches (ground mounts only). How heavy are solar panels? The distributed weight of a rooftop solar array is less than 3 pounds per square foot (equivalent to a few inches of snow). Due to the weight distribution, the solar array will not cause a roof to sag or bow. Do solar panels resist hail? Solar panels are faced with highly-durable tempered glass, which is rated to withstand a minimum of 1-inch hailstones at 50 mph direct strikes. Flatter roofs are more susceptible to hail damage due to the angle of impact, while roofs of 5:12 pitch or greater rarely suffer damage based on our experience. Learn more. What is the longevity of a solar panel? Solar panels are designed to produce power for decades. An average panel will degrade by about 0.5% or less per year. Most solar panel manufacturers guarantee at least 80% of the original performance for 25 years. What is the longevity of a solar inverter? Most solar power inverters are warrantied for at least 10 years and up to 25 years. Does the battery need to be indoors? Preferably. Even though some batteries are rated for outdoor use, lithium batteries need to be warm and will use energy for temperature regulation in the wintertime, reducing efficiency. Inside an attached garage or in a utility/mechanical/storage area is best. How large is the battery? Generally, consider the floor space needed to be equivalent to a full-size refrigerator (minimum 3 feet wide for wall space), depending on the system model and number of units installed.
  • New Construction
    Learn more about new construction planning from our detailed page about New Construction. Should I design/plan my roof for solar? Design your roof for solar panels by considering factors such as orientation, slope, and roofing material. A 5:12 to 9:12 pitch is ideal for excellent year-round performance and snow shedding. The roof needs a south-facing direction (SE, S, SW), not have shading (i.e. from trees), and not have pipes, flues or a chimney in the preferred solar locations. Simple roof designs like gable and skillion roofs are the most favorable for solar panel placement, while hipped roofs and complex roofs with dormers are unfavorable. Standing-seam metal or rubber shingles are the ideal roofing materials for long-term durability and ease of installation. Is ground-based solar better? Ground-mounted solar systems may be more favorable in some cases, offering better performance overall to maximize energy independence; they may not be feasible in certain situations such as urban areas, small lots, or steep terrain, and they have a higher cost in materials and labor. What electrical work is needed? To reduce costs for a retrofit, we will help you plan for a solar installation during the construction phase. This includes planning of the utility service equipment, main breaker panel, backup generator (if any), conduits for solar circuits, and equipment locations. Where to install the solar/battery power equipment? The best location for solar/battery power equipment is in the garage or utility/mechanical room. Batteries must be in a conditioned space that is preferably between 50 and 80 degrees (F) year-round. Should I plan to be off-grid? Off-grid power systems may be preferable in some situations, but it's not for everyone. Do thorough research to determine if off-grid living is right for you. If a grid-connection is readily available, it is usually favorable to have the additional power source connected. A solar and battery power system that also has a grid connection is called a backup power system. Other considerations for building? The single most effective way to reduce the size and cost of the power system, enhance self-sufficiency, and increase the comfort and longevity of your new home is to build for high efficiency. Focus on reducing heating costs through improved building efficiency and insulation. Choose a quality builder who is knowledgeable in energy conservation and building methods. Ensure the building envelope is airtight and thoroughly insulated. Consider a blower-door test to measure air-tightness. Choose a builder who prioritizes quality. While cost-efficiency is important, performance should always take precedence, especially if you're looking to build an energy-independent home. Look for a builder who has a good understanding of energy conservation and modern building methods and is willing to go beyond the legal minimum standards. Don't build a leaky house. During construction, pay special attention to details such as windows, doors, ductwork, and wall penetrations. Once complete, get a blower-door test to measure airtightness. A home that fails this test is not only energy inefficient but can also indicate poor construction quality and lead to problems over time. Insulate thoroughly and reduce thermal bridging. Use exterior insulation, structural insulated panels, insulated concrete forms, and similar construction materials that improve energy efficiency. Install a mechanical air exchanger to maintain air quality and regulate humidity. This addition is crucial in an airtight building, as it not only improves air quality but also enhances overall health and comfort. Prepare the electrical system for solar/battery/EV integration to avoid future retrofit costs. Place the main electrical panel in the garage or a mechanical room. Choose an electric tank water heater instead of an electric on-demand one. Gas or propane water heaters are acceptable if properly vented. Use heat pumps for heating and cooling, and if possible, consider heat-pump clothes dryers and water heaters. Install high-efficiency kitchen appliances, with induction cooktops being a preferred option. Consider geothermal only if it's appropriate for your location, as it can sometimes be excessively expensive and inefficient if not used correctly. Learn more at and
  • Energy Efficiency
    How much electricity do I use? Your utility power company will provide guidance on to read your bill and understand your consumption. In most cases, a monthly graph of your energy use will suffice, but if your utility has an online system to allow you to log in and view your usage this is a great way to learn in more detail. If you need an in-depth understanding of your home's individual electrical loads, have us install a smart home energy monitor that can identify your individual appliances and help you find issues. Is my usage above/below average? Seasonal use varies based on heating/cooling needs, but you can take your 12-month total kWh use to compare to the average. The average South Dakota home uses about 33 kWh per day / 1000 kWh per month / 12,000 kWh per year. It is normal to have higher bills in the winter, primarily due to heating (especially electric but also furnace fans), but if air conditioning in the summer this is also a major energy consumer. Heating and cooling represent the largest portion of energy consumption (by far) for most buildings. How do I reduce my power bills? Here are a few energy-saving tips: Reduce or eliminate air leaks, especially around door seals and windows. If achieving a very air tight home, remember that an air quality control system like an air exchanger will be needed. Improve insulation, especially in attics and around hot water lines. When replacing siding, this is a good opportunity to address issues and add insulation from the exterior. Know your major appliances and how much energy they consume. Heating, cooling, clothes dryers, old refrigerators/freezer, and pumping systems represent a significant majority of total energy consumption. Replace inefficient appliances such as old refrigerators and water heaters, replace incandescent lamps with LEDs, and replace furnace filters regularly. Understand your power bill and review your monthly usage. Compare with previous years. Contact your utility provider for support, and ask about incentives and rebates for energy efficiency improvements. Use a home energy monitor to learn about and observe your energy use, and quickly identify specific problem appliances.

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