[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Electricity Bill: T-8 vs PCF

> Are PCF and T-8 lights about the same in terms of electricity used?  I
know T-8s are more efficient
> than T-12 but could someone compare PCF and T-8?

Going by the Osram catalogue, there isn't a huge difference between T-8s and
PCFs.  T-8s do put out more lumens per watt when comparing the same
phosphor.  There is however a larger difference between phosphors, and
between lengths.

For example, comparing the 36 Watt T-8 and 18 Watt T-8 with the 36 Watt PCF
and a 55 Watt PCF, measuring lumens per watt (bigger number is better) we

Phosphor  36W T-8   18W T-8   36W PCF   55W PCF
11-860   90.3      72.2      76.4      82.7        6000K Lumilux 85 CRI
21-840   93.1      75.0      80.6      87.3        4000K Lumilux 85 CRI
12-950   65.3      55.5      52.8      54.5        5400K Lumilux de luxe 98
22-940   65.3      55.5      52.8      N/A        3800K Lumilux de luxe 96

If you're limited by hood length to using 18 Watt T-8s or 36/55 Watt PCFs,
then the PCFs generally win.  If however you're able to use 4' tubes, then
the T-8s win.  Choice of ballast will also affect the efficiency.

Unfortunately I can't make the same comparison for aquarium specific tubes,
as there is no reliable data available for them.



Suzy Jackson    http://www.suzyj.net    suzyj at suzyj_net