Chadds Ford Off Grid Solar System With Battery Storage Case Study
Solar integration in building design was the starting point for this 2022 project, where TerraSol Energies installed a 27kW solar array and a 163kWh battery bank to take a Pennsylvania homeowner completely off the grid.
The client wanted full energy independence, not a backup system that still depended on the utility. This case study breaks down the equipment, the battery bank, the cost, and what changes once a home runs on solar and stored power alone.
TL;DR
Complete energy independence — no reliance on the utility grid at all
Full control over energy source and storage
Cleaner power with minimal electromagnetic interference (EMI), compared to utility-supplied power
Reliable backup through winter via the propane generator when solar output drops
Seamless switching between solar, battery, and generator power with no disruption
Protection from utility rate hikes and outages since the home doesn't depend on the grid
Optimized energy capture via adjustable-tilt pole-mounted arrays for year-round efficiency
Long-term battery performance from lithium iron phosphate batteries (full discharge capability, ~10-year lifespan)
High homeowner satisfaction has been confirmed since the system went live in November 2022
Case Study: A 27kW Off Grid Solar System With Battery Storage in Chadds Ford, PA
In 2022, TerraSol Energies Inc, a leading solar energy company based in Chadds Ford, PA, undertook an extraordinary project for a client seeking complete energy independence.
By installing a 27kW solar power system coupled with 163kWh of Lithium Iron Phosphate batteries, the client's home was transformed into an off-grid powerhouse.
This is different from a grid-tied system, which stays connected to the utility and can pull power from the grid whenever needed. If you're still deciding between the two, TerraSol's comparison of off-grid vs. grid-tied systems breaks down the cost, control, and maintenance differences in plain terms.
Off-grid systems eliminate reliance on commercial power providers. Users maintain total control over their energy source and how it's stored, which matters most for remote locations where running utility lines isn't practical, or for homeowners who simply want backup power they don't depend on anyone else for.
Harnessing the Sun's Energy
At the heart of this groundbreaking project were the solar panels, strategically placed on the client's roof and two MTSolar pole mounted arrays. With a combined capacity of 27kW, these high-efficiency panels captured the sun's energy, converting it into usable electricity.
The pole-mounted arrays were particularly innovative, allowing the homeowner to optimize the tilt angle throughout the year for maximum efficiency.
Powering the Present and Future. To ensure an uninterrupted power supply, TerraSol integrated two Sol-Ark 15k bi-directional inverters into the system. These inverters efficiently converted the solar energy into usable electricity, seamlessly switching between the grid and the batteries as needed.
Additionally, a 20kW propane generator was installed to provide supplementary power during the winter months when daylight is shorter, and weather conditions may be less favorable.
System Components
Every off-grid solar system needs the same basic components, regardless of size:
Solar panels convert sunlight into electricity. High-efficiency solar panels produce more power output per square foot, which matters when roof space is limited.
Mounting system – secures the solar array to the roof or to the ground. Pole mounts are common for off-grid projects because they let the homeowner adjust the tilt angle throughout the year.
Inverter – converts the DC power the panels produce into AC power your house can actually use. This is what lets you run normal household appliances.
Batteries – store the energy the panels produce during the day so the household has power at night.
Service panel and wiring – electricity flows through the service panel to supply outlets and lights throughout the house.
For a deeper look at how the panels themselves function, TerraSol's breakdown of how a solar panel works walks through the process step by step. And once a system is installed, routine solar panel maintenance helps protect your investment and keep power output where it should be.
Embracing Energy Independence
The homeowner's decision to go off-grid had numerous advantages. Notably, the system allowed them to liberate themselves from reliance on the utility company, providing them with self-sufficiency and resilience.
With the combined capacity of the solar panels and batteries, the homeowner had high confidence that their energy needs would be met throughout the year, reducing both their carbon footprint and electricity costs.
Connect with our solar experts to check your eligibility.
Cleaner Power, Reduced EMI Noise
A remarkable benefit of this solar installation was the production of cleaner power with minimal electromagnetic interference (EMI) noise. Unlike power supplied by the utility company, which can suffer from electrical interference, the solar-powered system delivered a more stable and cleaner electrical signal.
This ensured the homeowner enjoyed a higher quality of power, reducing the risk of electrical disruptions and damage to sensitive electronics.
Client Satisfaction and Future Prospects
Since the system's completion in November 2022, the homeowner has expressed immense satisfaction with its performance. The seamless transition between solar power, battery storage, and occasional generator use during the winter months has surpassed their expectations.
TerraSol Energies takes immense pride in successfully executing this complex project and looks forward to undertaking more similar ventures in the future.
Lithium vs. Lead-Acid Batteries
Off-grid solar systems use deep-cycle batteries, since deep-cycle batteries are built to handle regular charging and discharging. Two types dominate the market:
Lithium batteries (most often lithium iron phosphate, or LFP) last about 10 years and can be discharged up to 100 percent safely. Most off-grid customers today choose lithium batteries for this reason — you get more usable capacity out of the same rated size.
Lead-acid batteries are cheaper upfront, but can only be discharged up to 50 percent. Discharge them further, and you shorten their lifespan. That means you need roughly double the rated capacity to get the same usable storage as lithium.
Lithium batteries are now the preferred choice for most off-grid solar systems for this reason alone. For a closer look at sizing and chemistry, TerraSol's strategic guide to residential energy storage covers how to determine the right battery bank for your household.
Why Homeowners Choose Off-Grid Living
Off-grid solar systems offer total energy independence for homeowners. Energy independence allows homeowners to generate and store their own electricity without depending on a utility company's rates, outages, or policy changes.
Common reasons homeowners choose off-grid living:
Remote locations where running grid power lines would cost more than installing solar
Backup power during a grid outage, without relying on a generator alone
Energy independence as a long-term plan to manage rising electricity costs
Control over their own power generation and storage, with no utility middleman
Lowering household energy consumption also helps any off-grid system run more efficiently. Cutting down appliance energy usage and simple ways to keep cool using less electricity both reduce the load your system has to cover, which can mean fewer panels and a smaller battery bank.
For the bigger picture on where the energy grid is headed, TerraSol's look at the future of the mid-Atlantic grid is worth a read.
What is the Cost of Going Off-Grid?
Off-grid solar systems require a substantial initial investment. Going off-grid can cost between $116,000 and $165,000 or more, depending on system size, battery bank, backup generator, and installation complexity.
That figure is higher than a comparable grid-tied system because an off-grid setup has to generate and store 100 percent of the household's energy needs. There's no utility line to fall back on and no net metering to offset the cost.
A few factors that move the estimate up or down:
System size (5kW to 21kW range covers most homes)
Lithium vs. lead-acid batteries
Backup generator as a secondary power source
Site conditions and how much wiring and mounting work the install requires
Tax credits and rebates can reduce the net cost. The federal solar tax credit currently allows a 30 percent deduction on qualified system costs, including battery storage.
If you're in TerraSol's service area, the PECO residential solar rebate is worth checking too. For a side-by-side look at upfront cost versus long-term savings, see TerraSol's breakdown of true solar costs and ROI.
Request a custom solar proposal now.
Conclusion
TerraSol Energies' 2022 project, which enabled a homeowner to go completely off-grid, stands as a testament to the remarkable capabilities of solar power coupled with battery storage.
With the installation of 27kW solar panels, 163kWh of Lithium Iron Phosphate batteries, Sol-Ark 15k bi-directional inverters, and a propane generator, the homeowner now enjoys energy independence and cleaner power.
TerraSol's commitment to innovative solutions continues to shape a greener and more sustainable future. Contact us today to get started on your solar project.
Frequently Asked Questions
What is an off grid solar system with battery storage?
It's a solar power setup that operates independently of the utility grid. Solar panels produce electricity, a battery bank stores it, and an inverter converts it to AC power for household use, with no utility connection or net metering.
How many solar panels do I need for an off-grid system?
It depends on your daily energy use and local sun hours. The average household uses about 30 kWh per day; the exact number of panels comes from dividing that figure by your panel wattage and expected sun hours. See TerraSol's panel sizing guide for the full calculation.
How many batteries does an off-grid solar system need?
It depends on usable capacity, not total capacity. Lithium batteries can be discharged up to 100 percent, while lead-acid batteries are limited to about 50 percent, so lithium systems generally need fewer batteries to store the same usable energy.
What's the difference between off-grid and grid-tied solar?
Off-grid systems have no utility connection and must generate and store all their own power. Grid-tied systems stay connected to the utility, can use net metering, and don't need as large a battery bank. TerraSol's comparison guide covers the trade-offs in detail.
