The Truth About LEDs

The Truth About LEDs

The Truth about LEDs - Good Light or Bag of Sh**e

We will spare you the "my mate got 3g per watt story" and shine a light on the current LED market! 

LEDs have well and truly landed in 2020, and there are some good ones about. We have broken down the market-leading LEDs to help you make a decision on what to buy.

Important Factors When Choosing an LED

Efficacy / Efficiency

'Some' LEDs can be more efficient than traditional HPS.

Heaps of LEDs are much less efficient to use than HPS lights. Efficiency is crucial; the higher the efficiency, the more of your light (watts) can be used for PAR (Plant Light.) Less efficiency means that a larger proportion of power (watts) will be wasted as heat or non-useable energy. 

For example, a 600W HPS single-ended light kit has the efficiency of around 1.35 μmol/j, whereas a 1000W 400v HPS Light is around 2.1 μmol/j. Top LEDs produce around 2.6-2.8 μmol/j

Output, PAR = PPF 

PPF stands for ‘photosynthetic photon flux’ and measures the amount of PAR (plant usable light) over 1 second. It's a useful measurement to use when calculating how much light your plant/room space needs. 


This brings us directly back to efficiency. In the same way that a car converts fuel into motion (MPG) is the same for how a light converts Power (Watts) into Light (PPF.) 

A more efficient light will be able to convert more power into usable light. This results in significantly less heat. 

It’s a common myth that all LEDs produce less heat than traditional HPS lights. Some do, and some don't. It's all down to efficiency.

Light Footprint 

Now you've found a light with excellent efficiency as well as a high PPF, you need to think about how that light is distributed over your growing canopy. 

Small Footprint - ideal for grow tents and smaller growing spaces. PPF can be concentrated downwards over a smaller growing space and used more efficiently.

+ Concentrated PPF

+ Great for grow tents as they will reflect wasted light

+ Great for lower wattage LEDs

+ Small and lightweight

+ Good for hobby and smaller grow tents

- Can provide too much-concentrated heat

- Poor coverage for open rooms or larger canopies

- Plants could grow unevenly if a light distribution from LED is poor.

Larger Footprint - we call these LED fixtures. Intended for larger scale and commercial applications. Providing a broader and more uniformed light footprint. Most commonly on bars and evenly distributed for optimal light coverage.

+ Uniform light spread

+ Even canopy growth

+ Wider heat distribution

+ Great for all growing styles 

- Some are not as lightweight or foldable. 

- Must pay attention to canopy hanging height to ensure adequate plant PPF exposure.

- Can be costly and expensive

The Stats 

Now you know what makes a great LED, let's look at the stats.

We have put together a list of market-leading LEDs including their efficiency, PPF and price. 

We have made 2 metrics of measuring how good your LED really is by using a price per PPF. This is simply how much PPF you get per £1 of money spent. 

Secondly is an energy rating. We personally think anything below 2.4 efficiency should really not be considered as an effective HPS replacement.

For any more information about our range of LED Lighting, please do not hesitate to get in touch with us today!

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