public class OpenXmlExcelTableExporter : IExcelTableExporter
    {
        public byte[] Execute(ExcelTableExporterModel model, IEnumerable data)
        {
            using (var result = new MemoryStream())
            {
                result.Write(Resources.EmptyTemplate, 0, Resources.EmptyTemplate.Length);
                result.Seek(0, SeekOrigin.Begin);

                using (var document = SpreadsheetDocument.Open(result, true))
                {
                    var sheet = document.WorkbookPart.WorksheetParts.First().Worksheet;
                    var sheetData = sheet.GetFirstChild<SheetData>();

                    var row = new Row();
                    sheetData.Append(row);

                    var cell = new Cell();
                    row.Append(cell);
                    cell.CellValue = new CellValue("Hello world!");
                    cell.DataType = CellValues.String;
                }

                return result.ToArray();
            }
        }
    }

byte[] Execute