The phrase "an inefficient source" is correct and usable in written English.
It can be used to describe a source of information, energy, or materials that does not operate effectively or optimally.
Example: "The outdated machinery proved to be an inefficient source of power for the factory, leading to increased operational costs."
Alternatives: "a suboptimal source" or "an ineffective source".
However the pulsed microwave radiation characteristic of radars is a rather inefficient source of energy.
This would be consistent with the observed increase in residual xylose concentrations with decreasing glucose feed (an already relatively inefficient source of PEP), the relative independency between residual xylose concentration and glycerol feed (a good source of PEP), and the decreased growth rate on xylose when Pal/Tal was introduced (drain on PEP for p-hydroxybenzoate production).
This result emphasizes that the traditional DEA model which treats the efficiency evaluation like a black box and ignores the internal processes is not appropriate for identifying inefficient DMUs and evaluating the degree of their inefficiencies since it provides little insight into the inefficient sources and the locations where the inefficiency may occur.
As highlighted in the problems with current meat production, animals are inefficient sources of meat.
This so-called carbon efficiency is a crucial factor that allows scientists to project carbon dioxide emissions, with more efficient energy sources contributing less to climate change than the more inefficient sources.
But steam, which was an inefficient and dangerous power source when Stirling started, had improved and would provide the power and scale to drive the Industrial Revolution.
Peat is however a notoriously inefficient energy source, so making use of geothermal heat was becoming a more feasible alternative as it has been shown achievable to use natural hot water supplies for house heating in close proximity to hot springs.
It is known from microwave ablation studies that a single large heat source is an inefficient means of delivering energy to a large volume of tissue.
