Here are 60 of the best, most-asked questions about solar, complete with detailed answers designed to be crawled establish your expertise.
The answers are structured for You by Er.Harwinder Singh Dhiman being clear, factual, and first-to-answer the question directly. They are tailored by Roop Solar by implicitly embedding our experience (since 2007), expertise (engineering-led), and B2B/EPC focus.
Category 1: Solar Energy Basics (The “Brain”)
1. Q: How do solar panels work?
A: Solar panels work by converting sunlight directly into electricity. Each panel contains photovoltaic (PV) cells, which are typically made of silicon. When sunlight (photons) strikes these cells, it excites electrons, creating a direct current (DC) of electricity. This DC electricity is then sent to an inverter.
2. Q: What is a solar inverter and what does it do?
A: A solar inverter is the “brain” of your solar system. It takes the variable Direct Current (DC) electricity produced by your solar panels and converts it into the stable Alternating Current (AC) electricity that powers your home, factory, or business. It also manages system performance and safety.
3. Q: What are the main types of solar systems?
A: There are three main types:
- On-Grid (Grid-Tie): This system is connected to the public electricity grid. It allows you to export surplus power to the grid (see Net Metering) and draw power from the grid when your panels aren’t producing, like at night.
- Off-Grid: This system is 100% independent and not connected to the grid. It requires a battery bank to store all the energy you need. It is ideal for remote areas.
- Hybrid: This is a combination of on-grid and off-grid. It’s connected to the grid but also has a battery backup, giving you the best of both worlds: savings from net metering and power during an outage.
4. Q: Do solar panels work on cloudy or rainy days?
A: Yes. Solar panels produce electricity from light, not heat. While direct sunlight is optimal, panels will still generate a significant amount of power on cloudy, rainy, or overcast days from diffused light. Production will be lower than on a bright, sunny day, but it does not drop to zero.
5. Q: Do solar panels work in the winter?
A: Yes, solar panels often work more efficiently in colder temperatures. Panel efficiency is slightly reduced by high heat. As long as the panels are clear of heavy snow, they will produce electricity very effectively, even on a cold, crisp winter day.
6. Q: What is the difference between monocrystalline and polycrystalline panels?
A:
- Monocrystalline (“Mono”): Made from a single, high-purity silicon crystal. They are more efficient (take up less space for the same power) and have a sleek black appearance.
- Polycrystalline (“Poly”): Made from multiple silicon fragments melted together. They are slightly less efficient and have a blue, speckled look. They are often a more cost-effective option.
7. Q: Do solar panels require a lot of maintenance?
A: No. Solar panels are extremely durable and require very little maintenance. The best practice is to clean them 2-4 times per year to remove dust, dirt, or bird droppings that can block light. In many parts of Punjab, dust is the main factor, so a simple cleaning schedule is all that’s needed.
8. Q: How long do solar panels last?
A: Solar panels are built to last for decades. Most high-quality panels come with a 25-year performance warranty. They will typically continue to produce electricity for 30 years or more, with a minor, gradual decrease in efficiency over their lifetime (called degradation).
9. Q: What is solar panel degradation?
A: Degradation is the small, natural decline in a solar panel’s power output over time. A good quality panel is warrantied to produce at least 80-85% of its original power output even after 25 years. This is a slow, predictable process.
10. Q: Will a solar system work during a power cut?
A: It depends on your system.
- Standard On-Grid systems will automatically shut down during a power cut. This is a safety feature to protect utility workers repairing the lines.
- Hybrid systems or Off-Grid systems with battery backup will provide power during an outage, keeping your essential lights and appliances running.
Category 2: Cost, Savings & ROI (The “Bottom Line”)
11. Q: How much does a solar system cost?
A: The cost depends on the system size (measured in kilowatts, kW), the quality of panels and inverters used, and the complexity of the installation. For a business, this is an investment in infrastructure, not a simple purchase. The best way to know the cost is to get a detailed site assessment and quotation from an experienced EPC company.
12. Q: What is the payback period for a solar system?
A: The payback period is the time it takes for your electricity bill savings to equal your initial investment. For commercial and industrial (C&I) clients, this is often very fast—typically between 3 to 6 years, depending on your electricity tariff and system size. After the payback period, the electricity is virtually free.
13. Q: How much money can I save with solar?
A: You can save up to 80-90% on your electricity bills. For a business, this has a direct, positive impact on your operating costs and profitability. The exact savings depend on your energy consumption, the size of your solar plant, and your local grid tariffs.
14. Q: What is “Net Metering”?
A: Net Metering is a billing mechanism for on-grid systems. When your solar panels produce more electricity than you are using, the extra power is exported to the grid. Your utility company gives you credit for this exported power, which you can use to offset the cost of power you draw from the grid at night.
15. Q: Are there government subsidies for solar?
A: Yes, the Indian government actively encourages solar adoption. For residential systems, the PM Surya Ghar: Muft Bijli Yojana provides significant central financial assistance. For commercial and industrial sectors, benefits like Accelerated Depreciation (AD) are available, which allows a business to claim a large portion of the asset’s value as depreciation in the first year, reducing tax liability.
16. Q: Does installing solar increase my property value?
A: Absolutely. A solar system is an asset that reduces a property’s operating costs. For a home, it’s a major selling point. For a commercial or industrial property, it’s a capital improvement that makes the building more valuable and efficient for any future owner or tenant.
17. Q: Are there financing options for solar?
A: Yes, many banks and financial institutions offer “solar loans” or “green financing” specifically for solar projects. For businesses, OPEX (Operating Expense) models are also popular, where you pay a third party for solar power at a rate lower than the grid, with zero upfront investment.
18. Q: What is the difference between a CAPEX and OPEX solar model?
A:
- CAPEX (Capital Expenditure): You (the business) own the solar plant. You make the upfront investment and all the savings are 100% yours. This offers the highest long-term ROI.
- OPEX (Operating Expenditure): A third party (an investor) pays for and owns the solar plant on your roof. You sign a Power Purchase Agreement (PPA) to buy electricity from them at a pre-decided, lower tariff for 15-25 years. This model requires zero investment from you.
19. Q: How is the size of a solar system (kW) determined?
A: The system size is based on three main factors:
- Your energy consumption (how many units, kWh, you use per month).
- Your available, shadow-free roof space.
- Your budget and investment goals.An expert engineer will analyze your electricity bills and conduct a site survey to recommend the optimal size.
20. Q: What are the hidden costs of solar installation?
A: With a transparent, experienced EPC company, there should be no “hidden” costs. Your quotation should be all-inclusive. Potential variable costs, which should be clearly discussed, might include significant roof strengthening (if needed) or long-distance trenching for wiring. Always choose a partner who is upfront about the entire project scope.
Category 3: Business, B2B & Industrial Solar (The “Expertise”)
21. Q: What is a “Solar EPC Company”?
A: EPC stands for Engineering, Procurement, and Construction. An EPC company (like Roop Solar) is a full-service partner that manages your entire solar project from start to finish. This includes:
- Engineering: Site analysis, system design, and technical drawings.
- Procurement: Sourcing all high-quality components (panels, inverters, structures).
- Construction: The complete installation, commissioning, and grid synchronization.
22. Q: Why should my factory or business install solar?
A: The number one reason is financial. It drastically cuts your largest operating cost: electricity. It gives you control over rising energy prices, provides a predictable ROI, and enhances your brand by showing you are a green, sustainable company.
23. Q: What is “B2B Solar Wholesale”?
A: B2B (Business-to-Business) Solar Wholesale is the business of supplying solar components—like panels, inverters, and mounting structures—in bulk to other businesses, such as local solar installers, retailers, and EPC companies. As a leading wholesaler since 2007, we provide our partners with quality products and technical support.
24. Q: My factory has a metal sheet roof. Can I install solar?
A: Yes, metal sheet roofs are excellent for solar installations. We use specialized, non-intrusive mounting structures that clamp or fasten securely to the roof purlins without compromising its waterproofing. It’s a very common and effective type of installation.
25. Q: What is Accelerated Depreciation for solar?
A: Accelerated Depreciation (AD) is a significant tax benefit for businesses in India. It allows you to claim a large percentage (as high as 80-100% in some cases) of the solar plant’s cost as depreciation in the very first year of installation. This greatly reduces your taxable income, improving your project’s payback period.
26. Q: How much roof space do I need for a 100kW solar plant?
A: As a general rule of thumb, you need approximately 100 square feet of shadow-free area for 1 kW of solar. Therefore, a 100 kW solar plant would require about 10,000 square feet of clear, shadow-free roof space.
27. Q: What is a “Power Purchase Agreement” (PPA)?
A: A PPA is the contract used in an OPEX or RESCO model. It’s a long-term agreement (e.g., 20 years) where you agree to buy the solar electricity produced on your roof from the system’s owner at a fixed (or indexed) price that is lower than your current grid tariff.
28. Q: How does solar work for a business that runs 24/7?
A: For a 24/7 operation, a grid-tie system is perfect. During the day, the solar plant will power your operations directly, cutting your grid consumption dramatically. At night, you will automatically draw power from the grid as usual. The system is designed to offset your daytime load, which is typically the largest, and delivers maximum savings.
29. Q: Can I use solar to run my heavy machinery?
A: Yes. The solar system doesn’t run machinery directly. It feeds AC power into your main electrical panel. Your building and machinery then draw power from that panel, just as they always have. The solar power simply replaces the power you would have otherwise bought from the grid, no matter the load.
30. Q: As a B2B partner, why should I buy from a wholesaler like Roop Solar?
A: Partnering with an established wholesaler (since 2007) gives you reliability. You get access to consistent, high-quality product inventory, competitive pricing, and most importantly, expert technical support from qualified engineers. We succeed when our installer partners succeed.
Category 4: Technology & Components (The “Nuts & Bolts”)
31. Q: What is a “string inverter” vs. a “microinverter”?
A:
- String Inverter: The most common type. A single inverter connects a “string” (group) of solar panels. It’s reliable, cost-effective, and ideal for roofs with no shading issues.
- Microinverter: A small inverter installed on the back of every single panel. They are more expensive but are excellent for complex roofs with shading, as the poor performance of one panel doesn’t affect the others.
32. Q: What is a solar battery and how does it work?
A: A solar battery stores the excess DC electricity your panels produce during the day instead of exporting it to the grid. When your panels stop producing (at night) or during a power cut, the battery releases this stored energy to power your home or business.
33. Q: Do I need a battery with my solar system?
A:
- For On-Grid: You do not need a battery. The grid acts as your “battery” via net metering.
- For Hybrid: You need a battery if your goal is to have power during a grid outage.
- For Off-Grid: A battery is essential and non-negotiable.
34. Q: What are the new types of solar panel technology?
A: New technologies are always emerging. TOPCon (Tunnel Oxide Passivated Contact) and HJT (Heterojunction) are two leading-edge technologies. They offer higher efficiencies (meaning more power in the same amount of space) and lower degradation rates than standard PERC cells.
35. Q: What are “bifacial” solar panels?
A: Bifacial panels can produce electricity from both sides of the panel. They capture direct sunlight on the front and reflected light (albedo) from the surface below (like a white roof or the ground) on the back. This can increase energy generation by 5-20%.
36. Q: What is a “Solar Mounting Structure”?
A: This is the foundational framework that holds your solar panels in place. It secures the panels to your roof or the ground and is engineered to withstand high winds, rain, and other environmental stresses. A properly designed structure is critical for the system’s 25+ year lifespan.
37. Q: How do I monitor my solar system’s performance?
A: All modern inverters come with remote monitoring. You can track your system’s live energy production, daily savings, and historical data through a simple app on your smartphone or a web portal. This allows you to see your investment at work in real-time.
38. Q: What does “Tier-1” solar panel mean?
A: “Tier-1” is not a measure of panel quality. It is a ranking of a manufacturer’s financial stability, based on their bankability and scale, as defined by services like BloombergNEF. While it’s a good indicator of a company that will be around to honor its warranty, it doesn’t automatically mean the panel is of the highest quality.
39. Q: What is an “ACDB” and “DCDB” in a solar system?
A:
- DCDB (Direct Current Distribution Box): This is a safety device. It collects the DC power from the solar panels and provides protection against surges and overcurrent before the power goes to the inverter.
- ACDB (Alternating Current Distribution Box): This box takes the AC power after it leaves the inverter and provides protection before it connects to your main power panel.
40. Q: What is a “Solar Tracker”?
A: A solar tracker is a mounting system used in large, ground-mounted solar farms. It automatically tilts the solar panels throughout the day to follow the sun’s path across the sky, just like a sunflower. This “tracking” can significantly increase energy generation compared to a fixed-tilt system.
Category 5: Installation & Process (The “How-To”)
41. Q: How long does a solar installation take?
A: This varies by system size.
- Residential (3-10kW): Typically 1 to 3 days for the physical installation.
- Commercial (50-100kW): May take 1 to 4 weeks.
- Industrial (1MW+): Can take several months.The total project timeline (including design, permits, and grid approval) will be longer.
42. Q: What is the process of getting a solar system?
A: A professional EPC company follows a clear process:
- Consultation: We understand your energy needs and goals.
- Site Survey: An engineer visits your property to measure the roof, check for shading, and assess the electrical setup.
- Design & Proposal: We create a custom engineering design and present a detailed financial proposal.
- Installation: Our in-house team completes the physical installation.
- Commissioning: We test the system and get it approved by the grid utility (net metering).
- Handover: We hand over the system to you and show you how to monitor it.
43. Q: Will you drill holes in my roof? Will it leak?
A: This depends on your roof type.
- RCC (Concrete) Roofs: We use elevated structures that sit on the roof, often without drilling.
- Metal Roofs: We use specialized clamps that attach to the seams, avoiding penetrations.If any penetration is required, a professional installer uses high-quality, weatherproof sealants and flashing to ensure a 100% leak-proof installation, guaranteed.
44. Q: What is a “shadow-free” area and why is it important?
A: A shadow-free area is a part of your roof that receives clear, unobstructed sunlight, especially during peak hours (e.g., 9 AM to 4 PM). Even a small shadow from a tree, chimney, or water tank on one panel can reduce the performance of the entire “string” of panels. A good design is critical to avoid this.
45. Q: What direction should solar panels face?
A: In the Northern Hemisphere, the ideal direction for solar panels to face is true South to maximize sun exposure throughout the day. However, East-West facing installations are also very effective, as they can capture more morning and afternoon sun, which may better match a building’s consumption pattern.
46. Q: What warranties come with a solar system?
A: A quality system comes with multiple warranties:
- Panel Performance Warranty: 25 years (guarantees output).
- Panel Product Warranty: 10-12 years (covers defects).
- Inverter Warranty: 5-10 years (can often be extended).
- Workmanship Warranty: 1-5 years (covers the installation itself).
47. Q: Who handles the government paperwork and net metering approval?
A: A full-service EPC company, like Roop Solar, handles 100% of the paperwork. This includes applications to your local utility (like PSPCL in Punjab) and any subsidy portal. We manage the entire process for you so it’s completely hassle-free.
48. Q: Why should I choose an experienced solar company (since 2007)?
A: A solar system is a 25-year asset. An experienced company (especially one founded in 2007) has survived market changes and has a long-term track record. It proves they use quality engineering, have stable B2B supply chains, and will be around to honor your warranties.
49. Q: Can I install solar panels myself (DIY)?
A: It is strongly discouraged. Solar installation involves high-voltage DC electricity, which is extremely dangerous. It also requires structural and electrical engineering to be done safely and correctly. Using a professional, licensed installer is essential for safety, performance, and warranty validation.
50. Q: What happens if I move? Can I take my solar panels with me?
A: It is technically possible, but rarely practical. The system is custom-designed for your roof, and the cost of removal and re-installation is high. It is almost always better to sell the solar system with the property, as it adds significant value and is a major selling point.
Category 6: Common Myths vs. Reality (The “Heart-Touch”)
51. Q: Myth: Solar is too expensive and not affordable.
A: Reality: This is the biggest misconception. Solar is an investment, not an expense. For a business, it’s one of the only investments with a guaranteed, predictable ROI (often 25-30%). With financing and OPEX models, you can start saving from day one with zero money down. The real question is: can you afford to keep paying high grid tariffs?
52. Q: Myth: Solar panels will damage my roof.
A: Reality: A professionally installed system protects your roof. The panels shield the roof from direct sun, rain, and hail, which can extend its life. An experienced installer (like an EPC) uses certified mounting techniques that are 100% leak-proof and structurally sound.
53. Q: Myth: Solar panels are fragile and break easily in hail.
A: Reality: Solar panels are incredibly tough. They are manufactured to meet strict international standards (like IEC 61215) which include impact tests. They are made with strong, tempered glass that can withstand hail, high winds, and heavy rain with ease.
54. Q: Myth: Solar energy is “unreliable” because the sun doesn’t shine at night.
A: Reality: This confuses “intermittent” with “unreliable.” Solar is extremely reliable—it predictably produces power every day. For an on-grid system, the grid provides power at night. For a hybrid system, a battery provides power. The solution is fully engineered for 24/7 reliability.
55. Q: Myth: I have to wait for “new technology” because solar is still improving.
A: Reality: Waiting is a financial mistake. Solar technology is already highly mature and efficient. Every month you wait, you are paying a 100% loss to the utility company. The savings you miss out on by “waiting” for a 5% better panel far outweigh the tiny benefit. The best time to invest was yesterday; the second best time is today.
56. Q: Myth: Manufacturing solar panels uses more energy than they produce.
A: Reality: This is false. The “Energy Payback Time” (EPBT) for a modern solar panel is typically between 1 to 2 years. Since the panel will operate for 25+ years, it will produce 15-25 times more clean energy than was used to manufacture it.
57. Q: Myth: Solar systems look ugly on a roof.
A: Reality: Modern solar installations are sleek and futuristic. New all-black panels and low-profile mounting systems blend beautifully with rooftops. Many people see a solar-paneled roof as a symbol of a smart, modern, and responsible home or business.
58. Q: Myth: Only hot, sunny states like Rajasthan benefit from solar.
A: Reality: Solar works exceptionally well across all of India, including Punjab. While sunny days are great, high heat can slightly reduce efficiency. Punjab’s climate is ideal. Germany, a global solar leader, gets less sun than most of India. It’s about light, not just heat.
59. Q: Myth: My electricity bill will become “zero” after installing solar.
A: Reality: Your bill will be drastically reduced, but rarely “zero.” You will still have to pay fixed monthly charges from the utility (meter rent, service fees). An honest EPC will set realistic expectations, which is saving 80-90% of your energy charges, not 100% of the total bill.
60. Q: Myth: All solar companies are the same.
A: Reality: This is the most dangerous myth. A solar system is a 25-year marriage. Choosing a new, inexperienced installer to save a few rupees can lead to failed systems, voided warranties, and a company that disappears in a few years. Choosing an established EPC company with a long history (e.g., since 2007) and real engineering expertise is the most important decision you will make.