Powerbi embed report - pass only space as url parameter value

Hi,

1.

I am trying to pass URL parameters to the  embed report in my application and couple of the parameters value expects a single space: 

'&rp:SubDepartmentIdList= &rp:DepartmentIdList= '

It does not display only space is not accepted as a passed parameter value. 

When I pass + instead of space, it takes it as + only, reference https://docs.microsoft.com/en-us/power-bi/paginated-reports/report-builder-url-pass-parameters

How can I acheive this.

2. Additionally, the embed report does not auto render when after execution of below statement from my app for null parameters:

var report = powerbi.embed(reportContainer, config); 

I have enabled the parameter to accept null values in the powerbi report builder.