An independent concept rebuild of apparent.com, unaffiliated with Apparent Inc. Built by Daniel Ramirez as an application for the Software Engineer role.

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Technology

PULSE

Power Utilization Leveraging Surplus Energy

Traditional data centre design wastes up to half its power. PULSE is the hardware stack that stops it.

Three things going wrong at once.

01

The dirty power tax

Raw grid power arrives carrying harmonics and reactive fluctuation. That excess is dissipated as heat in the processors, which costs uptime at one end and cooling at the other.

02

The AI surge

As AI workloads drive power density up, inefficiencies that were tolerable at 5 kW a rack stop being tolerable at 50.

03

The 2:1 power penalty

A conventional facility provisions two megawatts to deliver one megawatt of usable compute. The redundant feed sits idle, earning nothing, waiting for a failure.

Waveform shaping

What “cleaner power” actually means.

Every switch-mode supply in a rack draws current in short pulses near the voltage peak instead of sinusoidally. Fourier tells you what that is: a fundamental plus a stack of odd harmonics. Drag the slider.

Current waveform · 60 Hz, two cycles THD 32.2% / IEEE 519 limit 5%
Harmonic spectrum
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Raw grid power reaching the rack: 32.2% distortion, well past the IEEE 519 recommendation. That excess shows up as heat in transformers, in neutrals and in the processors themselves.

Why the third harmonic is the worst one

In a three-phase system the harmonics divisible by three — the triplens — arrive in phase on all three legs. Instead of cancelling in the neutral conductor the way the fundamental does, they add. An undersized neutral in an older server room runs hotter than any of the phases, which is not where anyone thinks to look.

Distortion is power that does no work

Harmonic current heats conductors, saturates transformer cores and inflates the apparent power the whole path has to be sized for, while contributing nothing to computation. It is the same argument as reactive power, one layer down: current you pay to carry and get nothing back from.

5% is not an aesthetic target

IEEE 519 recommends holding voltage distortion at or below 5% THD on a general distribution system. It is the number an interconnection agreement will cite, and the number a utility will measure at the meter when it wants to know whose fault the distortion is.

The stack

Three innovations.

Inline battery system

The battery sits in the path rather than beside it, forming an isolated microgrid with continuous delivery and no spin-up delay. There is no transfer event because there is nothing to transfer to.

Waveform shaping

Power factor is corrected and harmonic noise attenuated before the power reaches the processors. Cooler chips, higher uptime, less energy spent on distortion that never did any work.

True grid isolation

A fully isolated microgrid between the utility and the facility. Optional second feeds and generators become active resources instead of idle backup, so provisioned megawatts are actually used.

PULSE conditions the power. igOS decides what to do with it →