Design to Cost · Evaluate

Life Cycle Cost

Count the whole life, not the invoice: energy, maintenance, service, end-of-life — your product’s cost continues after delivery.

Time1 h
FormatSolo
StageEvaluate

Life Cycle Cost: what it is and why it works

Life Cycle Cost adds up everything the owner pays over the useful life of an asset, not just the purchase price: acquisition, installation, energy, consumables, planned and unplanned maintenance, downtime, spare parts, and decommissioning or disposal. Future costs are usually discounted to present value so options with different spending profiles can be compared fairly. Seen from the supplier side, the method asks which phases of the life your product wins and loses against the main alternative, and how the offer should change: a price move, a service contract, or a design change that shifts cost out of operation.

The method works because in many industrial categories the purchase price is a minor part of the total. For pumps, compressors, motors and fans in continuous duty, energy often dwarfs acquisition cost; for rotating equipment in remote sites, downtime and spares logistics can dominate. Buyers measured on purchase price will still pick the cheapest invoice unless someone presents the life cost convincingly. Life-cycle costing grew out of US defense acquisition practice and is framed for dependability work in IEC 60300-3-3. It supports Price-Value Alignment and the Business Case, and it corrects Make or Buy decisions that would otherwise ignore long-term operating effects.

What you need

The customer's life horizon and operating profile (hours per year, duty points, load factor)
Acquisition and installation cost for your product and the main alternative
Energy consumption, tariffs and expected escalation
Maintenance plan, spare parts, consumables and expected downtime
Discount rate used by the customer and end-of-life costs or residual value

What you get

Life cost per option, in present value, broken down by phase
The phases where your product wins and where it loses
Sensitivity to the key assumptions: energy price, hours, discount rate
An adapted offer: pricing, service package or design change
A customer-ready life cost comparison for sales and bid documents

When to use it

When purchasing optimizes purchase price and the customer pays the rest.

How to do it, step by step

Define the life horizon from the customer’s perspective.
Add purchase, energy, maintenance, consumables, downtime, end-of-life.
Compute the life cost for your product and the main alternative.
Identify the phases where you win and where you lose.
Adapt the offer: price, service contract, or design change.

Worked example: Pump selection for a municipal water treatment plant

Illustrative scenario — figures are realistic but not from a real company.

A pump manufacturer was bidding on six raw-water pumps for a treatment plant. A competitor offered a lower price. Each pump needs about 50 kW of hydraulic power and runs roughly 6,000 hours a year; the utility pays $0.10 per kWh and uses a 15-year horizon with a 7% discount rate.

The team compared its pump, at $31,000 and 75% wire-to-water efficiency, with the competitor's at $22,000 and 68%.
Input power came to about 66.7 kW versus 73.5 kW, a difference of 6.8 kW, or about 41,000 kWh and $4,100 per pump per year.
Discounted over 15 years at 7%, the energy difference is worth roughly $37,000 per pump, against a $9,000 higher price.
Maintenance and spare costs were similar; the team kept them in the model but they did not change the ranking.

Result. The life cost advantage was about $28,000 per pump, or $168,000 across six pumps. The bid presented the calculation with the utility's own assumptions and a sensitivity to energy price. The utility's evaluation added a life-cost criterion, and the lesson for the sales team was to bring the life cost to the buyer before the price discussion started.

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Common pitfalls and how to avoid them

Using your own assumptions instead of the customer's operating profile.Build the model with the customer's hours, tariffs, discount rate and horizon, and show sensitivity where they are uncertain.
Adding undiscounted future costs to today's price.Discount future cash flows to present value, or at least state clearly when a simple sum is used.
Omitting downtime and end-of-life costs because they are hard to estimate.Include them with a range; an estimated downtime cost is better than a silent zero.
Presenting life cost only after losing on price.Introduce life cost early, ideally in the specification or evaluation criteria, and tie it to the offer structure.

Frequently asked questions

What is included in life cycle cost?

Typically acquisition, installation and commissioning, energy, consumables, planned maintenance, repairs and spare parts, downtime or lost production, training, and decommissioning or disposal minus residual value. The exact list depends on the asset and on who bears each cost. The standard practice is to define the cost breakdown structure first, then estimate each element over the chosen horizon.

What is the difference between life cycle cost and total cost of ownership?

The terms overlap and are often used interchangeably. Life cycle cost is usually framed around an asset from concept to disposal, often in engineering and defense contexts. Total cost of ownership is more common in purchasing and IT and focuses on the buyer's costs of owning and using what they buy. Both aim to look beyond purchase price.

Should life cycle cost be discounted?

For decisions spanning several years, yes. Discounting converts future costs into present value so options with different spending profiles can be compared. Use the customer's or organization's discount rate, state it, and show how sensitive the ranking is to it. For short horizons or rough screening, an undiscounted sum can be acceptable if labeled.

Origin

Life-cycle costing — US Department of Defense practice, formalized 1960s–70s; IEC 60300-3-3.

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