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Alternatives to diesel? Some sites use microturbines or full turbines, and various of the local backup generators are LP or LNG and not diesel. Neither diesel

by Hoff 14y ago

Alternatives to diesel? Some sites use microturbines or full turbines, and various of the local backup generators are LP or LNG and not diesel. Neither diesel nor the gasoline blends are particularly stable during storage, unfortunately. Capstone claims a 10-second stabilization and transfer time for their microturbines, and has microturbines from tens of kilowatts up to a megawatt package. Con-Ed was (is?) running 155 MW and 174 MW turbines mounted on power barges, and they've had turbines around at least as far back as the 1920s. For some historical reading on turbine power generation: http://www.pondlucier.com/peakpower/blackstart/ http://www.pondlucier.com/peakpower/blackstart/ And yes, some of the fuel cell co-generation deployments look quite promising.

rdl 14y ago
Yeah, lots of little BTSes, relay stations, etc. use Lister LPG reciprocating engines rather than diesel because the long-term fuel stability is better, and because they're a lot more reliable at unattended automatic start than diesels, especially in the 10-20KW range (where the available diesels are particularly bad). I don't personally know of any datacenters using turbines for backup power. I don't know enough about turbines to know why that is -- maybe they're not available in smaller sizes, or have higher maintenance requirements, or higher capex per MW, or something else. The only turbines I've seen are cogen/prime power with grid backup, or marine.
- elithrar 14y ago
  > I don't personally know of any datacenters using turbines for backup power. I don't know enough about turbines to know why that is -- maybe they're not available in smaller sizes, or have higher maintenance requirements, or higher capex per MW, or something else. The only turbines I've seen are cogen/prime power with grid backup, or marine. They are just expensive; and then you also need a (safe) way to store gas on site. They also have small efficiency bands and therefore aren't always optimal for certain applications. Larger turbines also need a diesel generator to start them ("black start").
  - rdl 14y ago
    I don't think you'd use natural gas for backup power, you'd probably use Jet-A or actual diesel. (most turbines in the world probably run on Jet-A, being in actual jets; natural gas gets used for stationary power because it's cheaper and cleaner burning, sure, but that shouldn't be a major factor in a backup generator).
droithomme 14y ago
Gas turbines are a good choice. Mentioned elsewhere in this thread are concerns about storing gas on site and tremendous cost. Gas is not stored on site, it comes from the gas line, which doesn't stop working when the power goes out. Regarding cost, McDonalds has experimented with running their own gas turbines per restaurant because it can be cheaper than paying for an electric line in some areas. Here is a 13 yr old article about their initial experiments with gas turbines: http://findarticles.com/p/articles/mi_m0FZX/is_6_65/ai_55084209/ http://findarticles.com/p/articles/mi_m0FZX/is_6_65/ai_55084...
- rdl 14y ago
  Probably good in some areas (Canada near a pipeline but with bad roads), and bad in seismic areas like California (gas is likely to get shut off) or California (pge malinvestment likely to cause all gas lines to explode independent of earthquake).
- ibejoeb 14y ago
  Wow, neat concept for power-hungry businesses. I've been told that it's essentially impossible to go totally off-grid (in the US), i.e., you can do your own generation, but you'd sell it back into the grid and effectively pay net for consumption, which might turn out to be income. That could be for dependent on zoning, though, but I've heard this from a few engineers designing solar systems for residential.
ams6110 14y ago
Diesel stores pretty well, if you can keep water out of it, otherwise it's prone to algae formation. Big standby generation sites will filter their diesel to remove water, either continuously or periodically.
- toomuchtodo 14y ago
  You're referring to diesel/fuel polishing; its practically mandatory at sites storing large quantities of diesel fuel for extended periods of time for consumption purposes.

by Hoff 14y ago

rdl 14y ago

Yeah, lots of little BTSes, relay stations, etc. use Lister LPG reciprocating engines rather than diesel because the long-term fuel stability is better, and because they're a lot more reliable at unattended automatic start than diesels, especially in the 10-20KW range (where the available diesels are particularly bad). I don't personally know of any datacenters using turbines for backup power. I don't know enough about turbines to know why that is -- maybe they're not available in smaller sizes, or have higher maintenance requirements, or higher capex per MW, or something else. The only turbines I've seen are cogen/prime power with grid backup, or marine.

elithrar 14y ago
> I don't personally know of any datacenters using turbines for backup power. I don't know enough about turbines to know why that is -- maybe they're not available in smaller sizes, or have higher maintenance requirements, or higher capex per MW, or something else. The only turbines I've seen are cogen/prime power with grid backup, or marine. They are just expensive; and then you also need a (safe) way to store gas on site. They also have small efficiency bands and therefore aren't always optimal for certain applications. Larger turbines also need a diesel generator to start them ("black start").
- rdl 14y ago
  I don't think you'd use natural gas for backup power, you'd probably use Jet-A or actual diesel. (most turbines in the world probably run on Jet-A, being in actual jets; natural gas gets used for stationary power because it's cheaper and cleaner burning, sure, but that shouldn't be a major factor in a backup generator).

droithomme 14y ago

Gas turbines are a good choice. Mentioned elsewhere in this thread are concerns about storing gas on site and tremendous cost. Gas is not stored on site, it comes from the gas line, which doesn't stop working when the power goes out. Regarding cost, McDonalds has experimented with running their own gas turbines per restaurant because it can be cheaper than paying for an electric line in some areas. Here is a 13 yr old article about their initial experiments with gas turbines: http://findarticles.com/p/articles/mi_m0FZX/is_6_65/ai_55084209/ http://findarticles.com/p/articles/mi_m0FZX/is_6_65/ai_55084...

rdl 14y ago
Probably good in some areas (Canada near a pipeline but with bad roads), and bad in seismic areas like California (gas is likely to get shut off) or California (pge malinvestment likely to cause all gas lines to explode independent of earthquake).
ibejoeb 14y ago
Wow, neat concept for power-hungry businesses. I've been told that it's essentially impossible to go totally off-grid (in the US), i.e., you can do your own generation, but you'd sell it back into the grid and effectively pay net for consumption, which might turn out to be income. That could be for dependent on zoning, though, but I've heard this from a few engineers designing solar systems for residential.

ams6110 14y ago

Diesel stores pretty well, if you can keep water out of it, otherwise it's prone to algae formation. Big standby generation sites will filter their diesel to remove water, either continuously or periodically.

toomuchtodo 14y ago
You're referring to diesel/fuel polishing; its practically mandatory at sites storing large quantities of diesel fuel for extended periods of time for consumption purposes.