diff --git a/charger/fritzdect.go b/charger/fritzdect.go
new file mode 100644
index 000000000..89a752c33
--- /dev/null
+++ b/charger/fritzdect.go
@@ -0,0 +1,253 @@
+package charger
+
+import (
+	"crypto/md5"
+	"encoding/hex"
+	"encoding/xml"
+	"errors"
+	"fmt"
+	"net/url"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/andig/evcc/api"
+	"github.com/andig/evcc/util"
+	"github.com/andig/evcc/util/request"
+	"golang.org/x/text/encoding/unicode"
+)
+
+// AVM FritzBox AHA interface and authentification specifications:
+// https://avm.de/fileadmin/user_upload/Global/Service/Schnittstellen/AHA-HTTP-Interface.pdf
+// https://avm.de/fileadmin/user_upload/Global/Service/Schnittstellen/AVM_Technical_Note_-_Session_ID.pdf
+
+// FritzDECT charger implementation
+type FritzDECT struct {
+	*request.Helper
+	uri, ain, user, password, sid string
+	standbypower                  float64
+	updated                       time.Time
+}
+
+func init() {
+	registry.Add("fritzdect", NewFritzDECTFromConfig)
+}
+
+// NewFritzDECTFromConfig creates a fritzdect charger from generic config
+func NewFritzDECTFromConfig(other map[string]interface{}) (api.Charger, error) {
+	cc := struct {
+		URI          string
+		AIN          string
+		User         string
+		Password     string
+		SID          string
+		StandbyPower float64
+		Updated      time.Time
+	}{}
+
+	if err := util.DecodeOther(other, &cc); err != nil {
+		return nil, err
+	}
+
+	if cc.URI == "" {
+		cc.URI = "http://fritz.box"
+	}
+
+	if cc.AIN == "" {
+		return nil, errors.New("missing ain")
+	}
+
+	return NewFritzDECT(cc.URI, cc.AIN, cc.User, cc.Password, cc.SID, cc.StandbyPower, cc.Updated)
+}
+
+// NewFritzDECT creates FritzDECT charger
+func NewFritzDECT(uri, ain, user, password, sid string, standbypower float64, updated time.Time) (*FritzDECT, error) {
+	c := &FritzDECT{
+		Helper:       request.NewHelper(util.NewLogger("fritzdect")),
+		uri:          strings.TrimRight(uri, "/"),
+		ain:          ain,
+		user:         user,
+		password:     password,
+		standbypower: standbypower,
+		sid:          sid,
+	}
+	return c, nil
+}
+
+func (c *FritzDECT) execFritzDectCmd(function string) (string, error) {
+	// Refresh Fritzbox session id
+	if time.Since(c.updated).Minutes() >= 10 {
+		err := c.getSessionID()
+		if err != nil {
+			return "", err
+		}
+		// Update session timestamp
+		c.updated = time.Now()
+	}
+
+	parameters := url.Values{
+		"sid":       []string{c.sid},
+		"ain":       []string{c.ain},
+		"switchcmd": []string{function},
+	}
+
+	uri := fmt.Sprintf("%s/webservices/homeautoswitch.lua", c.uri)
+	response, err := c.GetBody(uri + "?" + parameters.Encode())
+	return strings.TrimSpace(string(response)), err
+}
+
+// Status implements the Charger.Status interface
+func (c *FritzDECT) Status() (api.ChargeStatus, error) {
+	// state 0/1 - DECT Switch state off/on (empty if unkown or error)
+	var state int64
+	resp, err := c.execFritzDectCmd("getswitchstate")
+
+	if err == nil {
+		state, err = strconv.ParseInt(resp, 10, 32)
+	}
+
+	// present 0/1 - DECT Switch connected to fritzbox (no/yes)
+	var present int64
+	resp, err = c.execFritzDectCmd("getswitchpresent")
+	if err == nil {
+		present, err = strconv.ParseInt(resp, 10, 64)
+	}
+
+	// power value in 0,001 W (current switch power, refresh aproximately every 2 minutes)
+	var power float64
+	if err == nil {
+		if resp, err = c.execFritzDectCmd("getswitchpower"); err == nil {
+			power, err = strconv.ParseFloat(resp, 64)
+		}
+	}
+
+	power = power / 1000 // mW ==> W
+	switch {
+	case present == 1 && state == 1 && power == 0:
+		return api.StatusA, err
+	case present == 1 && (state == 0 || (power > 0 && power <= c.standbypower)):
+		return api.StatusB, err
+	case present == 1 && power > c.standbypower:
+		return api.StatusC, err
+	default:
+		return api.StatusNone, errors.New("switch absent")
+	}
+}
+
+// Enabled implements the Charger.Enabled interface
+func (c *FritzDECT) Enabled() (bool, error) {
+	// state 0/1 - DECT Switch state off/on (empty if unkown or error)
+	resp, err := c.execFritzDectCmd("getswitchstate")
+
+	var state int64
+	if err == nil {
+		state, err = strconv.ParseInt(resp, 10, 32)
+	}
+
+	return state == 1, err
+}
+
+// Enable implements the Charger.Enable interface
+func (c *FritzDECT) Enable(enable bool) error {
+	cmd := "setswitchoff"
+	if enable {
+		cmd = "setswitchon"
+	}
+
+	// state 0/1 - DECT Switch state off/on (empty if unkown or error)
+	resp, err := c.execFritzDectCmd(cmd)
+
+	var state int64
+	if err == nil {
+		state, err = strconv.ParseInt(resp, 10, 32)
+	}
+
+	switch {
+	case err != nil:
+		return err
+	case enable && state == 0:
+		return errors.New("switchOn failed")
+	case !enable && state == 1:
+		return errors.New("switchOff failed")
+	default:
+		return nil
+	}
+}
+
+// MaxCurrent implements the Charger.MaxCurrent interface
+func (c *FritzDECT) MaxCurrent(current int64) error {
+	return nil
+}
+
+// CurrentPower implements the Meter interface.
+func (c *FritzDECT) CurrentPower() (float64, error) {
+	// power value in 0,001 W (current switch power, refresh aproximately every 2 minutes)
+	resp, err := c.execFritzDectCmd("getswitchpower")
+
+	var power float64
+	if err == nil {
+		power, err = strconv.ParseFloat(resp, 64)
+	}
+
+	// ignore standby power
+	power = power / 1000 // mW ==> W
+	if power < c.standbypower {
+		power = 0
+	}
+
+	return power, err
+}
+
+// Fritzbox helpers (based on ideas of https://github.com/rsdk/ahago)
+
+// getSessionID fetches a session-id based on the username and password in the connection struct
+func (c *FritzDECT) getSessionID() error {
+	uri := fmt.Sprintf("%s/login_sid.lua", c.uri)
+	body, err := c.GetBody(uri)
+	if err != nil {
+		return err
+	}
+
+	v := struct {
+		SID       string
+		Challenge string
+		BlockTime string
+	}{}
+
+	if err = xml.Unmarshal(body, &v); err == nil && v.SID == "0000000000000000" {
+		var challresp string
+		if challresp, err = createChallengeResponse(v.Challenge, c.password); err == nil {
+			params := url.Values{
+				"username": []string{c.user},
+				"response": []string{challresp},
+			}
+
+			if body, err = c.GetBody(uri + "?" + params.Encode()); err == nil {
+				err = xml.Unmarshal(body, &v)
+				if v.SID == "0000000000000000" {
+					return errors.New("invalid username (" + c.user + ") or password")
+				}
+				c.sid = v.SID
+			}
+		}
+	}
+
+	return err
+}
+
+// createChallengeResponse creates the Fritzbox challenge response string
+func createChallengeResponse(challenge string, pass string) (string, error) {
+	encoder := unicode.UTF16(unicode.LittleEndian, unicode.IgnoreBOM).NewEncoder()
+	utf16le, err := encoder.String(challenge + "-" + pass)
+	if err != nil {
+		return "", err
+	}
+
+	hash := md5.New()
+	if _, err = hash.Write([]byte(utf16le)); err != nil {
+		return "", err
+	}
+
+	md5hash := hex.EncodeToString(hash.Sum(nil))
+	return challenge + "-" + md5hash, nil
+}