Problem

At night, when I sneak around the house, I often bump into walls because it’s too dark.

Solution

I needed a light source that:

Must:

• be low intensity
• light the entire corridor
• emits no blue light (important for preserving night vision and deep sleep)
• require little to no maintenance
• be cheap to run

Could:

• also look decent

Idea

Over the year, I accumulated heaps of miscellaneous electronics of questionable value, including:

• 5V phone charger
• 5V red LED “fairy light” strip
• 5V day/night sensor
• plastic electrical box

I repurposed these into an automated night light system to gently illuminate the corridor.

It’s called the Peeway - because it illuminates the way to the only thing you’re likely doing when heading to the bathroom at night.

How expensive is it to run?

Using a USB power meter, I measured the power usage at about 1W.

Daily energy usage

1W × 12h = 12Wh(watt-hours)

Yearly energy usage

12Wh/day × 365days = 4380Wh = 4.38kWh

Cost to run

In my area, the price of 1kWh of energy is around 1 PLN which is 0.27 USD

Source: http://cena-pradu.pl/tabela.html

Yearly cost 3.38PLN/year 0.18USD/year

I’m fortunate enough to afford that.

At the time of writing this post, the peeway is running for more than a year and required no maintenance.

Build photos and demo

Power supply and day/night switch

Soldering them together

Power plug disassembly

Whole peeway power system attached to the wall

Demo

Peeway turned off during the day

Peeway forcibly turned on during the day

Peeway turned on during the night