help understanding DIY lights

[StonerZN]

Hi all.

So... I saw @SkunkPharmmake his own light so figured I would look into it... 
Nothing too crazy... Found the design I think will suit me (a 2' x 4' or 1.2 x 60 in English) on LEDGardener website here: https://ledgardener.com/diy-led-strip-build-designs-samsung-bridgelux/

Now under the 2'x 4' section, using the Samsung Q series, he reckons the given diagram will use 240W. 

2’x4′ Grow Space Builds

In a 2’x4′ space, we’ll aim for ~240 watts of power.

In the ingredient list, he specifies 14 x 2ft strips as below:

Samsung Q-Series LT-Q562A 2′ LED Strip Build – 2’x4′

Parts list:

14x Samsung LT-Q562A 2′ Strips ($168)

The digikey data sheet for the  LT Q562A however tells me each strip consumes 10W. 

my maths says 14 x 10W is 140W not 240W as he indicates. I would have expected to need to use 24 x 10W strips to reach 240W.

 

What am I missing? Don't wanna make an ass of myself with a comment on the site...

Any advice would be appreciated folks!

[Prom]

Your calculation is correct, but his isnt wrong either. He just uses a 240 driver for 140 watt load with a dimmer. Without a light meter... yeah, ok, but why  i would not use strips, but 2 288 V2 boards, around 32$ a piece, knocks 100$ off the bill, uses the full wattage of the driver.. still leaves you clueless what distance to hang... what is important  

using 24 of those Stripes, would be very expensive... using just 140 watts on a 1.2x0.6 is very ambitious, buds might be more on the fluff side 

[Cannabist]

On 3/9/2021 at 5:39 PM, Prom said:

using 24 of those Stripes

And a massive mission to mount and wire up