Springboot

After thinking about how to use the solar power my home generates in the most efficient way I realised that this is a generic problem. Effectively we have three types of devices in play :

• Generation Sources. eg. my solar panels, the house battery, the grid.
• Switchable Consuming Devices. eg. My car, a heat pump, the house battery. The load generated by these devices can be turned on/off.
• Background Load. The overall usage at the site. eg. my house load.

This general abstraction is a way of trying to come up with a common interface for each type of device so that we can easily add new devices as households get more connected.

As part of my ongoing solar project I wanted some basic weather forecast information to help make judgements around cloud coverage. The good people at OpenWeather provide an api with a free tier that includes forecasted cloud coverage data hourly for a couple of days.

The api returns a JSON structure that looks like this :

{
	"lat": 50.8,
	"lon": 0.027,
	"timezone": "Europe/London",
	"timezone_offset": 0,
	"current": {
		"dt": 1644836705,
		"sunrise": 1644822797,
		"sunset": 1644858426,
		"temp": 281.32,
		"feels_like": 277.84,
		"pressure": 997,
		"humidity": 80,
		"dew_point": 278.08,
		"uvi": 0.98,
		"clouds": 75,
		"visibility": 10000,
		"wind_speed": 6.69,
		"wind_deg": 250,
		"weather": [
 			{
				"id": 803,
				"main": "Clouds",
				"description": "broken clouds",
				"icon": "04d"
			}
		]
	},
	"hourly": [
	{
		"dt": 1644836400,
		"temp": 281.32,
		"feels_like": 277.47,
		"pressure": 997,
		"humidity": 80,
		"dew_point": 278.08,
		"uvi": 0.98,
		"clouds": 75,
		"visibility": 10000,
		"wind_speed": 7.9,
		"wind_deg": 242,
		"wind_gust": 12.16,
		"weather": [
		{
			"id": 803,
			"main": "Clouds",
			"description": "broken clouds",
			"icon": "04d"
		}
		],
		"pop": 0.05
	},
	.
	.
	.

With 48 of those hourly snippets covering the next two days.