Posts

100Kwh-runny-24x7-solar and BESS calculations

How to Choose Solar Panels and Batteries to Run a 100kWh Load 24/7: Full Guide with Examples

/0 Comments/in /by

If you’re planning to power a 100kWh load continuously (24/7) using solar panels and a battery energy storage system (BESS), it’s not as simple as just multiplying watts. You need to factor in weather conditions, seasonal sunlight availability, cloudy days, and energy efficiency. This blog will guide you step-by-step on how to size your system properly using formulas, examples, and visual data.

???? What You’ll Learn:

  • How to calculate required solar panel capacity
  • Why yearly weather data is critical
  • How to handle cloudy days and winter months
  • Battery sizing for different backup durations
  • Example formulas and real-world values

???? Step 1: Understand Your Load

Let’s say your system must support a 100 kWh per hour load.

  • 24 hours/day × 100 kWh = 2,400 kWh per day
  • That’s your daily energy demand from solar + battery.

???? Step 2: Analyze Your Location’s Solar Irradiance

Your geographic location heavily influences how much sunlight you receive—measured in Peak Sun Hours (PSH).

LocationPeak Sun Hours
Phoenix, USA6.5 PSH
New Delhi, India5.5 PSH
London, UK2.8 PSH

???? You can get this data from tools like PVWatts, NASA SSE, or Solcast.

???? Step 3: Calculate Required Solar Panel Capacity

Formula:

textCopyEditRequired Solar Capacity (kW) = Daily Load (kWh) ÷ (PSH × Derating Factor)
  • Daily Load = 2,400 kWh
  • Derating factor (system losses) = ~0.8
SeasonPSHRequired Solar Capacity
Summer6.52,400 ÷ (6.5 × 0.8) ≈ 462 kW
Winter4.02,400 ÷ (4.0 × 0.8) ≈ 750 kW
Cloudy Days2.52,400 ÷ (2.5 × 0.8) ≈ 1,200 kW
Solar panels required for 100KWh running 24/7


????️ Why Consider Cloudy Days?

Even if your area has high annual irradiance, you’ll still face days with poor sun exposure. For mission-critical applications, your system must:

  • Be oversized for worst-case scenarios.
  • Include battery backup for 1–3 days.
  • Use hybrid systems (e.g., gensets or grid backup) if needed.

❄️ Considerations for Winter Months

Winter brings:

  • Lower sun angles
  • Shorter daylight
  • Snow cover (for northern regions)

???? This reduces effective PSH and increases your dependence on storage or supplemental power.

⚡ Step 4: Size the BatteryEnergy Storage System for Backup

Battery Energy Storage System should store enough energy to power the load during non-sunny hours or failures.

Formula:

textCopyEditBattery Capacity (kWh) = (Daily Load × Days of Autonomy) ÷ (DoD × Efficiency)
  • Daily Load = 2,400 kWh
  • Depth of Discharge (DoD) = 0.8
  • Round-trip Efficiency = 0.9
Backup DurationRequired Battery Capacity
1 Day2,400 ÷ (0.8 × 0.9) ≈ 3,333 kWh
2 Days4,800 ÷ (0.8 × 0.9) ≈ 6,667 kWh
3 Days7,200 ÷ (0.8 × 0.9) ≈ 10,000 kWh
Battery Backup required for 100Wh 24/7 Running


✅ Tips for Choosing Solar Panels

  • ✔️ Use Tier-1 panels with high efficiency (≥21%)
  • ✔️ Consider bifacial panels if space allows
  • ✔️ Use anti-reflective coating for dust-heavy areas
  • ✔️ Install with adjustable tilt for seasonal optimization

✅ Tips for Choosing Batteries Cells for BESS

???? Hybrid Solutions for Reliability

When powering a 100kWh continuous load, consider a hybrid setup:

  • ???? Solar + Battery + Diesel: For industrial backup
  • ???? Solar + Grid + Battery: For grid-tied systems
  • ????️ Solar + Wind + Battery: For off-grid redundancy

???? Real Use Case Example

Scenario:

  • Location: Northern India
  • PSH (winter): 4 hours
  • Load: 100kWh × 24 = 2,400kWh/day
  • Solar Size = 2,400 ÷ (4.0 × 0.8) = 750 kW
  • Battery for 2 days = 2,400 × 2 ÷ (0.8 × 0.9) ≈ 6,667 kWh

???? FAQs

Q: Can I go without batteries?

A: Only if your load is flexible or you remain connected to the grid.

Q: Should I oversize the battery or the solar array?

A: Both, depending on your climate. Cloudy regions need higher solar oversizing.

Q: What’s better—LFP or NMC batteries?

A: LFP is safer and more stable for stationary storage.

???? Conclusion

Designing a solar + battery system for a 100kWh 24/7 load isn’t just about matching numbers—it’s about planning for the worst day of the year, not the best. Location-specific solar data, battery autonomy, system losses, and seasonal variations must all be part of your sizing strategy.

AC Coupled BESS

What is AC Coupled BESS? Core Components, How It Works & Its Advantages

/0 Comments/in /by

As the world races toward a cleaner future, storing renewable energy efficiently is no longer optional—it’s essential. At the core of this transition is the Battery Energy Storage System (BESS). Among its many forms, the AC Coupled BESS stands out for its flexibility, reliability, and ease of integration. Whether you’re expanding an existing solar setup or starting fresh, this powerful configuration could be the key to true energy freedom. In this post, we’ll uncover what makes AC coupling special—and why it might just be the smarter choice for your energy journey.

What is AC Coupled BESS?

AC Coupled BESS (Battery Energy Storage System) refers to a type of energy storage architecture where the battery system is connected to the electrical grid or load side through an alternating current (AC) interface. Unlike DC-coupled systems, where the battery shares a common DC bus with solar inverters, AC-coupled systems require separate inverters for both solar (or other generation sources) and battery storage.

AC coupling is a smart, scalable solution often used in retrofit projects, hybrid systems, and microgrids, offering flexibility in design and control.

Core Components of AC Coupled BESS

An AC Coupled BESS typically consists of the following key components:

1. Battery Pack

The heart of the system – stores energy chemically and discharges it as needed. Battery types include:

  • Lithium-ion (most common)
  • LFP (Lithium Iron Phosphate)
  • NMC (Nickel Manganese Cobalt)
  • Lead-acid (less common today)

2. Battery Management System (BMS)

Monitors and protects the battery cells by managing parameters like voltage, temperature, and charge/discharge rates. Prevents overcharging, deep discharging, and ensures system longevity.

3. Battery Inverter (Bidirectional Inverter)

This converts DC power from the battery into AC for grid compatibility, and vice versa during charging. Also known as a PCS (Power Conversion System) in utility-scale deployments.

4. Energy Meter

Monitors and measures the energy flow to and from the battery, PV system, grid, and loads. Helps in performance monitoring and utility compliance.

5. EMS (Energy Management System)

The brain of the system – it manages how and when the battery charges or discharges based on load demand, time-of-use pricing, grid signals, and PV generation.

6. Grid Connection / Load Panel

Where the system connects to the facility’s electrical infrastructure, enabling energy import/export and onsite consumption.

How Does AC Coupled BESS Work?

Here’s a simple breakdown of how an AC Coupled BESS operates:

✅ Energy Generation (Solar or Wind)

A solar PV inverter generates AC electricity from the sun during daylight hours.

✅ AC Flow to Battery Inverter

Excess AC electricity not consumed on-site is routed to the battery inverter, which converts it to DC to charge the battery.

✅ Battery Charging

The battery stores energy as DC power, which is managed by the BMS for optimal health and safety.

✅ Discharge Mode

When the load demand exceeds generation (e.g., at night), the battery inverter converts stored DC power back to AC to power the home or facility.

✅ Grid Interaction

Depending on system configuration, the BESS can import power from or export excess energy to the grid, enabling peak shaving, backup power, and participation in demand response programs.

Advantages of AC Coupled BESS

AC Coupled systems offer several compelling advantages:

1. Retrofit-Friendly

Easier to integrate into existing solar PV systems. No need to modify the existing DC infrastructure.

2. Modular & Scalable

You can scale solar and battery systems independently. Ideal for adding more storage or generation capacity later.

3. Enhanced Redundancy

Separate inverters mean that if the solar or battery inverter fails, the other can still operate independently.

4. Flexible Control Strategies

AC coupling allows integration of diverse energy sources (wind, genset, hydro) and supports complex control logics using EMS.

5. Supports Microgrids & Off-Grid Applications

Crucial for backup power and remote areas. Works well in microgrids with multiple power sources and fluctuating load demands.

6. Time-of-Use Optimization

Charge batteries when electricity is cheap, and discharge during peak pricing. This helps reduce electricity bills significantly.

7. Grid Services Compatibility

Advanced systems can provide frequency regulation, voltage support, and participate in ancillary service markets.

AC Coupled vs. DC Coupled BESS – Quick Comparison

FeatureAC Coupled BESSDC Coupled BESS
InvertersSeparate for PV and batteryShared inverter
Retrofit CapabilityExcellentModerate to low
System ComplexityHigherLower
Energy Conversion LossesSlightly higherLower
ScalabilityVery highTied to PV system
Control FlexibilityHighLimited

Where is AC Coupled BESS Used?

  • Commercial and Industrial facilities needing power backup or time-of-use optimization.
  • Remote microgrids with multiple sources of energy.
  • Retrofit projects adding batteries to an existing solar system.
  • Utility-scale grid support installations where power export, voltage regulation, and load shifting are required.

Conclusion

AC Coupled BESS is a versatile and future-proof energy storage architecture. While it involves slightly more components and costs compared to DC coupling, the flexibility, redundancy, and modularity it offers make it a favorite for professionals designing hybrid systems, microgrids, and energy-resilient facilities.

Whether you’re an engineer, energy consultant, or business owner exploring storage solutions – understanding how AC coupled BESS works is key to making smarter energy decisions.

Need help sourcing or evaluating AC Coupled BESS systems?
As a New Energy Consultant with over 13 years in China’s energy sector, I help global clients source reliable BESS products, conduct factory audits, and ensure full compliance with international standards.

???? Let’s connect on LinkedIn or reach out to discuss your project requirements.

Why UL 1973 Certification Matters – Protect Your Battery, Your Business & Your Customers

/2 Comments/in /by

UL 1973 certification ensures battery safety, trust, and market approval. Learn why it’s essential for energy storage systems and how it protects people and businesses.

⚡ Introduction: Don’t Just Build a Battery — Build Trust

In today’s world, batteries are everywhere — in homes, cars, solar systems, and factories. But one big question remains:

???? Is your battery safe?

That’s where UL 1973 Certification comes in. It’s not just a piece of paper. It’s proof that your battery won’t catch fire, fail under stress, or put lives at risk.

UL 1973 is a mark of trust, a badge of safety, and a green light for global sales.

✅ What is UL 1973 Certification?

UL 1973 is a safety standard for stationary batteries — the ones used in solar systems, home backup, telecom towers, EV charging stations, and more.

It tests the complete battery system — not just the cells — including:

  • Battery Packs
  • BMS (Battery Management System)
  • Wiring & Enclosures
  • System Safety Features

This ensures the whole system is strong, smart, and safe.

???? Why UL 1973 is So Important

????️ 1. Protects Lives

UL 1973-certified batteries go through fire tests, short circuit tests, pressure tests, and more. This reduces the risk of fires, explosions, or breakdowns.

You’re not just protecting a product — you’re protecting homes, families, and workers.

???? 2. Opens Doors to Global Markets

Governments, big buyers, and EPC contractors trust UL 1973. In many places, you can’t even sell your battery without it.

Want to grow your business worldwide? Start with this certification.

???? 3. Builds Customer Confidence

When your battery has the UL 1973 mark, customers know it’s safe. It gives them peace of mind — and makes your product stand out from the rest.

???? 4. Meets Tender and Project Requirements

Many big energy projects now require UL 1973. Without it, your battery may not even qualify. Don’t miss out because of one missing label.

???? What Does UL 1973 Actually Test?

UL 1973 looks at how your battery behaves under real conditions:

  • ???? Short circuit and overcharge safety
  • ???? Fire resistance and thermal management
  • ????️ Extreme temperature performance
  • ???? Smart BMS functions (to cut off danger early)
  • ???? Mechanical strength (shock, vibration, impact)
  • ???? Water and dust protection

???? This is not just about ticking boxes — it’s about keeping people safe.

???? Real Examples Where UL 1973 is a Must

  • Home energy storage (solar batteries)
  • Office & commercial backup systems
  • Factories and industrial machines
  • Telecom towers and remote areas
  • EV charging stations and microgrids
  • Containerized energy storage solutions

In short — anywhere a battery works hard, UL 1973 matters.

???? What Happens If You Skip UL 1973?

  • ❌ Safety risks and accidents
  • ❌ Rejection from projects and tenders
  • ❌ Low customer trust
  • ❌ Insurance problems
  • ❌ Legal issues in some countries

⚠️ A small saving today can cost you your entire business tomorrow.

???? How UL 1973 Helps You Grow Faster

With UL 1973Without UL 1973
Trusted by buyersQuestioned by clients
Approved for tendersDisqualified early
Lower insurance riskHigher operational risk
Global sales accessLimited market reach

This one certification can make or break your brand’s reputation and reach.

???? What Other Certifications Go With It?

✔️ Get the right mix of certifications and become a global battery brand.

???? Final Words: Safety First, Always

When someone uses your battery — in their home, in their car, in a hospital, or on a mountain — they trust you with their life.

UL 1973 isn’t just a technical standard. It’s a promise.

A promise that you care about safety, quality, and doing the right thing.
A promise that you’re ready for the global stage.

???? Need Help Getting UL 1973?

As a battery sourcing and quality expert, I help companies:

  • Get UL 1973-ready designs
  • Find the right testing labs in China
  • Avoid delays and rejections
  • Choose certified components for packs, BMS, and more

???? Let’s connect and get your battery certified, safe, and ready for success.