[Jonny H]

It is a big challenge. 600W is not enough - about the same heat output as 12 tea candles burning. For a little context, a petrol heater is 2000W and a classic mini heater is 2500W.

We designed the electric heating system for the Singer DLS, which led to the development of the high output alternator for the 911 and 964 engines (see our website). The DLS has 1600W of heat which is marginal for ‘real world’ use. It is deemed enough for a supercar that will live a cherished life. 1600W is 125A continuous which has the effect of pulling the battery voltage down. This results in the current going up so you end up in a voltage / current death spiral unless the load is managed.

The solution involves smart / adaptive software control of the heating power based on demand and alternator output. We have a similar control strategy in our electric AC so we are working to adapting this to the heat solution.