Buying a generator is step one. The value shows up when the unit starts on demand, carries your load, and stays healthy for years. That outcome has a cost profile you can plan for. This guide maps the true cost of ownership so you can compare new and used options, fuel types, commissioning, and maintenance with real numbers. Examples come from projects we support in Colorado, Florida, Texas, and nationwide.
Generator Source supports facilities from 20 kW to 4000 kW. Our teams in Brighton near Denver, Jacksonville, Pensacola, and Austin handle sizing, logistics, installation support, load bank testing, and ongoing service. The goal is simple. Power on when it matters with a cost plan you can defend.
What outage risk really costs
Start with the impact. List critical loads and estimate the cost per hour if those loads go dark. Include lost production, restart time, safety risks, penalties, and spoilage. Even modest sites can face five figures per hour when HVAC, process equipment, and IT are offline.
A properly sized generator and a matched automatic transfer switch reduce both the duration and severity of loss. Facilities that exercise and load bank test on a schedule see fewer start up surprises. The avoided cost becomes part of your return on investment, not just an insurance idea.
- Estimate cost per hour of downtime for your critical process
- Multiply by expected outage hours in a typical year for your region
- Compare that number to annualized ownership cost for the generator and ATS
- Add risk reduction benefits from testing and maintenance
The line items that make up total cost of ownership
Plan for more than the purchase price. A realistic budget includes the items below. Numbers vary by site and region, but the list itself holds up across industries.
- Acquisition price for new or used equipment
- Freight based on weight, dimensions, and route permits
- Rigging and craning to the pad with site access verified
- Fuel system or gas tie in and required clearances
- ATS and controls integration with your electrician
- Commissioning and witnessed load bank with a written report
- Preventative maintenance across the year
- Parts and consumables over five to ten years
- Fuel maintenance for diesel or storage planning for propane
- Remote monitoring if required by your team or insurer
- Resale value or redeployment flexibility at end of life
A used 800 kW diesel in a sound attenuated enclosure can save 30 to 50 percent compared to new. Freight should be quoted by dimension and route rather than miles alone. Rigging should match lift height and reach at your site. Commissioning should include settings, alarms, and a witnessed load bank with a signed report. PM planning should match your usage pattern, criticality, and local codes.
New or used with lifecycle math
New units bring current engine and controls technology, factory warranty, and options set to your spec. Lead times can run weeks to months depending on brand and configuration. If your project timeline is fixed, confirm build and ship dates before you commit.
Low hour used units from a reputable dealer deliver immediate availability and lower capital cost. The key is documentation and proof. Look for verified hours, a multi point inspection, and a full load bank test with a report. Over a five year window, a used unit paired with a strong PM plan often delivers a lower cost per protected hour, especially when an outage is a near term risk.
What we verify on every used unit:
- Nameplate data on engine, alternator, and controller
- Hour meter reading supported by condition, records, or ECU data when available
- 31 point inspection in our shop with corrective work noted
- Full load bank test to rated kW with voltage, frequency, and temperature logged
- Accessories present and functional such as block heater and battery charger
Fuel type and operating cost
Match fuel to application, loads, and service reality in your region.
Diesel
Strong transient response for motor loads and step changes. Plan for proper exercise, periodic load banking, and fuel maintenance. Diesel units that run at light load can experience wet stacking. Load banking raises exhaust temperature and burns off deposits.
Natural gas
Clean operation and long runtimes when utility gas is available. Verify gas pressure and BTU content at the meter. Confirm pipe sizing and regulator performance during commissioning.
Propane
A good option for remote sites without natural gas. Size storage for realistic runtimes and delivery schedules. Confirm local codes on tank location and setbacks.
We model runtime cost with your local fuel prices rather than national averages. That keeps the plan honest for Denver and the Front Range, Duval County and the Gulf Coast, and Central Texas.
Commissioning protects warranty and ROI
Commissioning is where ownership truly starts. It is also where many projects risk long term issues if steps are missed. A complete process covers fuel, cooling air, electrical settings, alarms, and a witnessed test.
What our commissioning covers:
- Site checks for clearances, airflow, and safe egress
- Fuel quality verification and gas pressure checks
- Breaker settings and controller configuration
- ATS function test with transfer and retransfer timing
- Remote monitoring setup when required
- Witnessed load bank at stepped loads with a signed report for your files
You leave with proof that voltage, frequency, and temperature remained within spec across load steps. That report is useful for your insurer, your auditor, and future resale.
Maintenance that prevents low load damage
Low hours do not guarantee health. Engines that sit or idle still age. A disciplined maintenance plan keeps reliability high and protects value.
- PM1. Inspection focused service with oil and coolant samples. Scheduled monthly, quarterly, or semi annually based on risk
- PM2. Annual service that includes PM1 plus oil and filter changes and a periodic load bank test
- Load bank testing. Raises exhaust temperatures to prevent carbon buildup and wet stacking on diesel units
- Fuel maintenance. Polishing and testing for diesel storage. Delivery planning for propane
- Records. Keep signed reports, lab results, and corrective actions in one place
Our preventative maintenance plans are built around how your facility operates. We can schedule after hours, coordinate with production, and bring rental power if your process cannot stop.
Field snapshots
These short examples reflect the variety of sites we support. Names and details are simplified for privacy, while the technical steps remain accurate.
Denver manufacturing line
A 600 kW diesel arrived with a 12 lead alternator. Our technicians reconfigured from 208 V to 480 V, verified controller settings, and performed a witnessed load bank. The line passed a building test within the same week. The team chose a used unit to shorten risk exposure ahead of a seasonal ramp.
Jacksonville healthcare facility
A 500 kW natural gas generator was installed with a new ATS and remote monitoring. Commissioning included gas pressure checks, alarm mapping, and a full function transfer test. The facility updated its maintenance plan to PM2 with quarterly exercises to align with internal policy.
Austin data workflow center
A 1000 kW diesel was deployed after a utility event. The unit was in stock and shipped within days. After placement with a crane, commissioning and a witnessed load bank confirmed performance. Remote monitoring alerts now feed the site team and our service desk.
How to read a listing with confidence
Skip the fluff and go straight to proof. The most important source of truth is the nameplate and the data plates on the engine, alternator, and controller.
Check these items every time:
- Verified hours that match condition and records
- Brand with deep parts support such as Caterpillar, Cummins, MTU, Generac, Kohler, HIPOWER, or Multiquip
- Alternator configuration. A 12 lead reconfigurable alternator adds flexibility for 480 V, 240 V, or 208 V
- Controller model, inputs and outputs, and remote monitoring options
- Enclosure type. Weather protected or sound attenuated to meet local noise rules
- Fuel system details. Base tank size or day tank plan and required clearances
- Emissions rating where applicable for permitting
- Accessories present such as block heater, battery charger, motorized louvers, and external breaker
If a detail is missing, ask for the data plate photo and the test report. A complete file is a sign of a careful seller.
Checklist you can use today
Use this quick checklist to organize your plan. It fits small sites and complex campuses.
- Confirm critical loads and acceptable voltage dip
- Run a load calculation with a qualified engineer
- Decide on fuel based on runtime, logistics, and local pricing
- Select new or used based on lead time and risk window
- Verify 12 lead alternator if future voltage changes are likely
- Budget for freight, rigging, commissioning, and PM
- Require a witnessed load bank with a signed report
- Set PM1 and PM2 schedules with calendar holds
- Enable remote monitoring with alert routing
- Keep all reports and lab results for insurance and resale
Why teams choose Generator Source
We support every major brand from 20 kW to 4000 kW. Each used unit receives a 31 point inspection and a full load bank test in our shops. Our EGSA certified technicians handle sizing support, rigging coordination, commissioning, and maintenance. Branches in Colorado, Florida, and Texas allow fast site walks and service response across the Mountain West and the Southeast.
- Browse live inventory at generatorsource.com/inventory/
- Learn about generator service at generatorsource.com/generator-service/
- Review preventative maintenance options at generatorsource.com/preventative-maintenance/
- Contact our team at generatorsource.com/contact/
Frequently asked questions
How fast can you ship to Colorado, Florida, or Texas
In stock units can ship within days. The exact window depends on route permits, crane scheduling, and site access. We plan timelines with your team before the order is placed.
Can you help with installation and commissioning
Yes. We coordinate with your electrical contractor, verify pads and clearances, support ATS integration, and perform commissioning with a witnessed load bank. You receive a signed report.
What size generator do I need for large motor loads
We run a load calculation that considers running load, starting current, and the voltage dip your process can accept. This prevents nuisance trips and protects equipment.
Can I change output voltage later
If the alternator is a 12 lead reconfigurable design, a qualified technician can change voltage. We confirm nameplate ratings and perform a verification test after changes.
How do I keep a diesel generator healthy with light usage
Exercise on schedule, include periodic load bank testing, and maintain fuel quality. Our PM2 plan includes a load bank so exhaust temperatures remain high enough to prevent deposits.