Generate Image with Microsoft .NET Chart Controls Library without Control

Is it possible to generate images (jpeg, png, etc) using the Microsoft Chart Controls library without instantiating a WinForm or ASP.NET Control class? All the examples I have seen utilize a control component. I need to create a library which contains simple methods that take data to be plotted and returns a new chart image. Examples:

public byte[] GeneratePlot(IList<SeriesData> series)
{
    // generate and return JPEG
}
public void GeneratePlot(IList<SeriesData> series, Stream outputStream)
{
    // generate JPEG and write to stream
}

If it is not possible:

1. would you recommend creating/disposing a new chart control each time the user calls the GeneratePlot() method?
2. is there another .NET library (preferably free) that you would recommend?

Thanks