After observing a recent episode of the popular TV show "Ice Road Truckers", I was inspired to create a solution for one of the more dangerous scenarios that these drivers face. I've learned from this TV series just how important it is that the diesel engines in these trucks are kept running. At the extremely frigid temperatures these trucks are driven in stopping the engine for only a matter of minutes can seriously jeopardize the driver’s chances of re-starting it. Not being able to start or re-start the engine in this environment can pose a serious threat to the driver’s life. The solution that I propose is to employ some type of thermal battery using a PCM (phase change material), such as erythritol which possesses a rather high latent heat of fusion with a melting temperature near the operating temperature of a diesel truck engine. While running the engines heat would be used to melt, and keep in a liquefied state, a sufficient amount of the PCM. This could be done by passing the engine coolant or exhaust gasses through a special heat exchanger and keeping the liquefied PCM stored in a large insulated containment vessel. When needed a coil buried within the insulated containment vessel would be used to pass coolant through the melted PCM to extract the heat. Pressure to drive the coolant would be created by an electric water pump which would send the warmed coolant on through to the engine block. Using a surprisingly small amount of a PCM possessing a high latent heat of fusion could supply a significant amount of heat. Enough to help get a frozen diesel started or at least keep a driver warm until help arrives.